diff --git a/helm/templates/_storage.tpl b/helm/templates/_storage.tpl
new file mode 100644
index 00000000000..39a3df089d6
--- /dev/null
+++ b/helm/templates/_storage.tpl
@@ -0,0 +1,82 @@
+#
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+{{/*
+Effective tablet storage volumes as a YAML list of {name, size, storageClass}:
+tablet.storage.volumes when non-empty, otherwise a single legacy entry built from
+tablet.storage.size / tablet.storage.storageClass. Each volume is mounted at
+/tmp/fluss/<name>, so the legacy entry keeps the original /tmp/fluss/data path.
+Usage:
+  include "fluss.tablet.storage.volumes" . | fromYamlArray
+*/}}
+{{- define "fluss.tablet.storage.volumes" -}}
+{{- if .Values.tablet.storage.volumes -}}
+{{- toYaml .Values.tablet.storage.volumes -}}
+{{- else -}}
+- name: data
+  size: {{ .Values.tablet.storage.size }}
+  storageClass: {{ .Values.tablet.storage.storageClass }}
+{{- end -}}
+{{- end -}}
+
+{{/*
+Comma-separated data.dirs value for server.yaml, derived from the effective volume
+mount paths.
+Usage:
+  include "fluss.tablet.storage.dataDirs" .
+*/}}
+{{- define "fluss.tablet.storage.dataDirs" -}}
+{{- $paths := list -}}
+{{- range (include "fluss.tablet.storage.volumes" . | fromYamlArray) -}}
+{{- $paths = append $paths (printf "/tmp/fluss/%s" .name) -}}
+{{- end -}}
+{{- join "," $paths -}}
+{{- end -}}
+
+{{/*
+Validation errors for tablet.storage.volumes.
+Usage:
+  include "fluss.storage.validateError" .
+*/}}
+{{- define "fluss.storage.validateError" -}}
+{{- $messages := list -}}
+{{- $names := list -}}
+{{- range .Values.tablet.storage.volumes -}}
+  {{- if not .name -}}
+    {{- $messages = append $messages "tablet.storage.volumes: every entry must set name" -}}
+  {{- else -}}
+    {{- if has .name $names -}}
+      {{- $messages = append $messages (printf "tablet.storage.volumes: duplicate volume name %q" .name) -}}
+    {{- end -}}
+    {{- if or (eq .name "fluss-conf") (eq .name "sasl-config") (hasPrefix "secret-" .name) -}}
+      {{- $messages = append $messages (printf "tablet.storage.volumes: volume name %q collides with a chart-managed volume (fluss-conf, sasl-config, secret-*)" .name) -}}
+    {{- end -}}
+    {{- if not (regexMatch "^[a-z0-9]([-a-z0-9]*[a-z0-9])?$" .name) -}}
+      {{- $messages = append $messages (printf "tablet.storage.volumes: volume name %q must be a lowercase DNS-1123 label (^[a-z0-9]([-a-z0-9]*[a-z0-9])?$)" .name) -}}
+    {{- end -}}
+    {{- if not .size -}}
+      {{- $messages = append $messages (printf "tablet.storage.volumes: entry %q must set size" .name) -}}
+    {{- end -}}
+    {{- $names = append $names .name -}}
+  {{- end -}}
+{{- end -}}
+{{- if and .Values.tablet.storage.volumes (hasKey (.Values.configurationOverrides | default dict) "data.dirs") -}}
+  {{- $messages = append $messages "configurationOverrides must not set data.dirs when tablet.storage.volumes is used: the chart renders data.dirs from the volume list" -}}
+{{- end -}}
+{{- join "\n" $messages -}}
+{{- end -}}
diff --git a/helm/templates/_validate.tpl b/helm/templates/_validate.tpl
index d79221c97f7..52d5644efa8 100644
--- a/helm/templates/_validate.tpl
+++ b/helm/templates/_validate.tpl
@@ -41,6 +41,7 @@ Usage:
 {{- $messages = append $messages (include "fluss.security.validateError" .) -}}
 {{- $messages = append $messages (include "fluss.metrics.validateError" .) -}}
 {{- $messages = append $messages (include "fluss.secrets.validateError" .) -}}
+{{- $messages = append $messages (include "fluss.storage.validateError" .) -}}
 
 {{- $messages = without $messages "" -}}
 {{- join "\n" $messages -}}
diff --git a/helm/templates/configmap.yaml b/helm/templates/configmap.yaml
index bfaf0a74c91..0f31d096f68 100644
--- a/helm/templates/configmap.yaml
+++ b/helm/templates/configmap.yaml
@@ -28,6 +28,13 @@ data:
     {{ $key }}: {{ tpl (printf "%v" $val) $ }}
     {{- end }}
 
+    {{- if .Values.tablet.storage.volumes }}
+
+    ### Storage
+
+    data.dirs: {{ include "fluss.tablet.storage.dataDirs" . }}
+    {{- end }}
+
     ### Security
 
     {{- $internalProtocol := include "fluss.security.listener.protocol" (dict "context" .Values "listener" "internal") | trim -}}
diff --git a/helm/templates/sts-tablet.yaml b/helm/templates/sts-tablet.yaml
index 5407b2a6a95..d0c6affeeb6 100644
--- a/helm/templates/sts-tablet.yaml
+++ b/helm/templates/sts-tablet.yaml
@@ -164,8 +164,10 @@ spec:
           volumeMounts:
             - name: fluss-conf
               mountPath: /opt/conf
-            - name: data
-              mountPath: /tmp/fluss/data
+            {{- range (include "fluss.tablet.storage.volumes" . | fromYamlArray) }}
+            - name: {{ .name }}
+              mountPath: /tmp/fluss/{{ .name }}
+            {{- end }}
             {{- if (include "fluss.security.jaas.required" .) }}
             - name: sasl-config
               mountPath: /etc/fluss/conf
@@ -182,9 +184,11 @@ spec:
           configMap:
             name: fluss-conf-file
         {{- if not .Values.tablet.storage.enabled }}
-        - name: data
+        {{- range (include "fluss.tablet.storage.volumes" . | fromYamlArray) }}
+        - name: {{ .name }}
           emptyDir: {}
         {{- end }}
+        {{- end }}
         {{- if (include "fluss.security.jaas.required" .) }}
         {{- include "fluss.security.jaas.volumes" . | nindent 8 }}
         {{- end }}
@@ -196,12 +200,14 @@ spec:
         {{- end }}
   {{- if .Values.tablet.storage.enabled }}
   volumeClaimTemplates:
+    {{- range (include "fluss.tablet.storage.volumes" . | fromYamlArray) }}
     - metadata:
-        name: data
+        name: {{ .name }}
       spec:
         accessModes: [ "ReadWriteOnce" ]
         resources:
           requests:
-            storage: {{ .Values.tablet.storage.size }}
-        storageClassName: {{ .Values.tablet.storage.storageClass }}
+            storage: {{ .size | toYaml }}
+        storageClassName: {{ if .storageClass }}{{ .storageClass | toYaml }}{{ end }}
+    {{- end }}
   {{- end}}
diff --git a/helm/tests/storage_test.yaml b/helm/tests/storage_test.yaml
new file mode 100644
index 00000000000..dac4c979aa6
--- /dev/null
+++ b/helm/tests/storage_test.yaml
@@ -0,0 +1,277 @@
+#
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+suite: tablet-storage
+templates:
+  - templates/sts-tablet.yaml
+  - templates/configmap.yaml
+  - templates/NOTES.txt
+tests:
+  - it: renders a single emptyDir named data by default
+    asserts:
+      - contains:
+          path: spec.template.spec.volumes
+          content:
+            name: data
+            emptyDir: {}
+        template: templates/sts-tablet.yaml
+      - contains:
+          path: spec.template.spec.containers[0].volumeMounts
+          content:
+            name: data
+            mountPath: /tmp/fluss/data
+        template: templates/sts-tablet.yaml
+      - notExists:
+          path: spec.volumeClaimTemplates
+        template: templates/sts-tablet.yaml
+      - notMatchRegex:
+          path: data["server.yaml"]
+          pattern: 'data\.dirs:'
+        template: templates/configmap.yaml
+
+  - it: renders the legacy single claim from size and storageClass
+    set:
+      tablet.storage.enabled: true
+      tablet.storage.size: 20Gi
+      tablet.storage.storageClass: fast
+    asserts:
+      - equal:
+          path: spec.volumeClaimTemplates
+          value:
+            - metadata:
+                name: data
+              spec:
+                accessModes: [ "ReadWriteOnce" ]
+                resources:
+                  requests:
+                    storage: 20Gi
+                storageClassName: fast
+        template: templates/sts-tablet.yaml
+      - notContains:
+          path: spec.template.spec.volumes
+          content:
+            name: data
+            emptyDir: {}
+        template: templates/sts-tablet.yaml
+      - notMatchRegex:
+          path: data["server.yaml"]
+          pattern: 'data\.dirs:'
+        template: templates/configmap.yaml
+
+  - it: renders one claim, one mount, and data.dirs per configured volume
+    set:
+      tablet.storage.enabled: true
+      tablet.storage.volumes:
+        - name: data-0
+          size: 100Gi
+          storageClass: fast
+        - name: data-1
+          size: 200Gi
+    asserts:
+      - equal:
+          path: spec.volumeClaimTemplates
+          value:
+            - metadata:
+                name: data-0
+              spec:
+                accessModes: [ "ReadWriteOnce" ]
+                resources:
+                  requests:
+                    storage: 100Gi
+                storageClassName: fast
+            - metadata:
+                name: data-1
+              spec:
+                accessModes: [ "ReadWriteOnce" ]
+                resources:
+                  requests:
+                    storage: 200Gi
+                storageClassName: null
+        template: templates/sts-tablet.yaml
+      - contains:
+          path: spec.template.spec.containers[0].volumeMounts
+          content:
+            name: data-0
+            mountPath: /tmp/fluss/data-0
+        template: templates/sts-tablet.yaml
+      - contains:
+          path: spec.template.spec.containers[0].volumeMounts
+          content:
+            name: data-1
+            mountPath: /tmp/fluss/data-1
+        template: templates/sts-tablet.yaml
+      - matchRegex:
+          path: data["server.yaml"]
+          pattern: 'data\.dirs: /tmp/fluss/data-0,/tmp/fluss/data-1'
+        template: templates/configmap.yaml
+
+  - it: renders data.dirs for a single-entry volume list
+    set:
+      tablet.storage.enabled: true
+      tablet.storage.volumes:
+        - name: fast-0
+          size: 50Gi
+          storageClass: "1234"
+    asserts:
+      - matchRegex:
+          path: data["server.yaml"]
+          pattern: 'data\.dirs: /tmp/fluss/fast-0'
+        template: templates/configmap.yaml
+      - equal:
+          path: spec.volumeClaimTemplates[0].spec.storageClassName
+          value: "1234"
+        template: templates/sts-tablet.yaml
+
+  - it: renders data.dirs when configurationOverrides is nulled out
+    set:
+      configurationOverrides: null
+      tablet.storage.enabled: true
+      tablet.storage.volumes:
+        - name: data-0
+          size: 100Gi
+    asserts:
+      - notFailedTemplate: {}
+        template: templates/NOTES.txt
+      - matchRegex:
+          path: data["server.yaml"]
+          pattern: 'data\.dirs: /tmp/fluss/data-0'
+        template: templates/configmap.yaml
+
+  - it: renders one emptyDir per volume when storage is disabled
+    set:
+      tablet.storage.volumes:
+        - name: data-0
+          size: 100Gi
+        - name: data-1
+          size: 100Gi
+    asserts:
+      - contains:
+          path: spec.template.spec.volumes
+          content:
+            name: data-0
+            emptyDir: {}
+        template: templates/sts-tablet.yaml
+      - contains:
+          path: spec.template.spec.volumes
+          content:
+            name: data-1
+            emptyDir: {}
+        template: templates/sts-tablet.yaml
+      - notExists:
+          path: spec.volumeClaimTemplates
+        template: templates/sts-tablet.yaml
+
+  - it: keeps extraVolumes and extraVolumeMounts after the storage entries
+    set:
+      tablet.storage.enabled: true
+      tablet.storage.volumes:
+        - name: data-0
+          size: 100Gi
+      tablet.extraVolumes:
+        - name: scratch
+          hostPath:
+            path: /mnt/scratch
+      tablet.extraVolumeMounts:
+        - name: scratch
+          mountPath: /mnt/scratch
+    asserts:
+      - contains:
+          path: spec.template.spec.volumes
+          content:
+            name: scratch
+            hostPath:
+              path: /mnt/scratch
+        template: templates/sts-tablet.yaml
+      - equal:
+          path: spec.template.spec.containers[0].volumeMounts
+          value:
+            - name: fluss-conf
+              mountPath: /opt/conf
+            - name: data-0
+              mountPath: /tmp/fluss/data-0
+            - name: scratch
+              mountPath: /mnt/scratch
+        template: templates/sts-tablet.yaml
+
+  - it: fails when a volume entry has no size
+    set:
+      tablet.storage.enabled: true
+      tablet.storage.volumes:
+        - name: data-0
+    asserts:
+      - failedTemplate:
+          errorMessage: "VALUES VALIDATION:\ntablet.storage.volumes: entry \"data-0\" must set size"
+        template: templates/NOTES.txt
+
+  - it: fails when a volume entry has no name
+    set:
+      tablet.storage.enabled: true
+      tablet.storage.volumes:
+        - size: 100Gi
+    asserts:
+      - failedTemplate:
+          errorMessage: "VALUES VALIDATION:\ntablet.storage.volumes: every entry must set name"
+        template: templates/NOTES.txt
+
+  - it: fails on duplicate volume names
+    set:
+      tablet.storage.enabled: true
+      tablet.storage.volumes:
+        - name: data-0
+          size: 100Gi
+        - name: data-0
+          size: 100Gi
+    asserts:
+      - failedTemplate:
+          errorMessage: "VALUES VALIDATION:\ntablet.storage.volumes: duplicate volume name \"data-0\""
+        template: templates/NOTES.txt
+
+  - it: fails on a volume name that is not a DNS-1123 label
+    set:
+      tablet.storage.enabled: true
+      tablet.storage.volumes:
+        - name: bad_Name
+          size: 100Gi
+    asserts:
+      - failedTemplate:
+          errorMessage: "VALUES VALIDATION:\ntablet.storage.volumes: volume name \"bad_Name\" must be a lowercase DNS-1123 label (^[a-z0-9]([-a-z0-9]*[a-z0-9])?$)"
+        template: templates/NOTES.txt
+
+  - it: fails on a chart-reserved volume name
+    set:
+      tablet.storage.enabled: true
+      tablet.storage.volumes:
+        - name: sasl-config
+          size: 100Gi
+    asserts:
+      - failedTemplate:
+          errorMessage: "VALUES VALIDATION:\ntablet.storage.volumes: volume name \"sasl-config\" collides with a chart-managed volume (fluss-conf, sasl-config, secret-*)"
+        template: templates/NOTES.txt
+
+  - it: fails when configurationOverrides also sets data.dirs
+    set:
+      tablet.storage.enabled: true
+      tablet.storage.volumes:
+        - name: data-0
+          size: 100Gi
+      configurationOverrides:
+        data.dirs: /elsewhere
+    asserts:
+      - failedTemplate:
+          errorMessage: "VALUES VALIDATION:\nconfigurationOverrides must not set data.dirs when tablet.storage.volumes is used: the chart renders data.dirs from the volume list"
+        template: templates/NOTES.txt
diff --git a/helm/values.yaml b/helm/values.yaml
index de9c8eb42e0..715a897dad8 100644
--- a/helm/values.yaml
+++ b/helm/values.yaml
@@ -43,6 +43,18 @@ tablet:
     enabled: false
     size: 1Gi
     storageClass:
+    # Multi-disk (JBOD): one PVC per entry, mounted at /tmp/fluss/<name>. When
+    # non-empty, this list takes precedence over size/storageClass above and the
+    # chart renders `data.dirs` with all mount paths in server.yaml.
+    # NOTE: volumeClaimTemplates are immutable - enabling this on an existing
+    # release requires recreating the tablet StatefulSet (see the Helm docs page).
+    volumes: []
+    # - name: data-0
+    #   size: 100Gi
+    #   storageClass: fast
+    # - name: data-1
+    #   size: 100Gi
+    #   storageClass: fast
   # Readiness probe configuration for rolling upgrade gate.
   # The probe talks to the LOCAL tablet server (127.0.0.1:client-port) and
   # asks it to forward a getClusterHealth RPC to the Coordinator over the
diff --git a/website/docs/install-deploy/deploying-with-helm.md b/website/docs/install-deploy/deploying-with-helm.md
index 4a483e14a74..289d1f6dcb8 100644
--- a/website/docs/install-deploy/deploying-with-helm.md
+++ b/website/docs/install-deploy/deploying-with-helm.md
@@ -465,6 +465,10 @@ making rotation fully hands-off.
 | `tablet.storage.enabled` | Enable persistent volume claims for TabletServer | `false` |
 | `tablet.storage.size` | Tablet persistent volume size | `1Gi` |
 | `tablet.storage.storageClass` | Tablet storage class name | `nil` (uses default) |
+| `tablet.storage.volumes` | Multi-disk volume list; takes precedence over `size`/`storageClass` | `[]` |
+| `tablet.storage.volumes[*].name` | Volume name; mounted at `/tmp/fluss/<name>` | Required |
+| `tablet.storage.volumes[*].size` | Persistent volume size for this disk | Required |
+| `tablet.storage.volumes[*].storageClass` | Storage class name for this disk | `nil` (uses default) |
 
 ### Resource Parameters
 
@@ -711,6 +715,40 @@ tablet:
     storageClass: fast-ssd
 ```
 
+#### Multiple Disks per Tablet Server (JBOD)
+
+Tablet servers can spread data across multiple local disks via the `data.dirs`
+configuration. Declare one volume per disk under `tablet.storage.volumes`; each
+entry becomes its own PersistentVolumeClaim mounted at `/tmp/fluss/<name>`, and
+the chart renders `data.dirs` with all mount paths in `server.yaml`:
+
+```yaml
+tablet:
+  storage:
+    enabled: true
+    volumes:
+      - name: data-0
+        size: 100Gi
+        storageClass: fast-ssd
+      - name: data-1
+        size: 100Gi
+        storageClass: fast-ssd
+```
+
+When `volumes` is set it takes precedence over the single-disk `size` and
+`storageClass` keys, and `configurationOverrides` must not set `data.dirs`
+itself. The server ignores the default `data.dir` whenever `data.dirs` is
+configured.
+
+:::warning
+Kubernetes forbids changing the `volumeClaimTemplates` of an existing
+StatefulSet. To switch an existing release from the single-disk layout to
+`volumes` (or to change the volume list), delete the tablet StatefulSet while
+keeping its pods and claims (`kubectl delete statefulset tablet-server
+--cascade=orphan`) before upgrading, or install a fresh release. Data on the
+old single PVC is not migrated to the new volume layout automatically.
+:::
+
 Configure remote storage:
 
 ```yaml