diff --git a/web/app/components/workflow/skill/constants.ts b/web/app/components/workflow/skill/constants.ts
index ccf6cc736b..e25bd7442f 100644
--- a/web/app/components/workflow/skill/constants.ts
+++ b/web/app/components/workflow/skill/constants.ts
@@ -27,3 +27,7 @@ export const NODE_MENU_TYPE = {
 } as const
 
 export type NodeMenuType = (typeof NODE_MENU_TYPE)[keyof typeof NODE_MENU_TYPE]
+
+export const SIDEBAR_MIN_WIDTH = 240
+export const SIDEBAR_MAX_WIDTH = 480
+export const SIDEBAR_DEFAULT_WIDTH = 320
diff --git a/web/app/components/workflow/skill/sidebar.tsx b/web/app/components/workflow/skill/sidebar.tsx
index b581056280..7ad36f3dc6 100644
--- a/web/app/components/workflow/skill/sidebar.tsx
+++ b/web/app/components/workflow/skill/sidebar.tsx
@@ -1,12 +1,47 @@
+'use client'
+
 import type { FC, PropsWithChildren } from 'react'
+import { useDebounceFn } from 'ahooks'
 import * as React from 'react'
+import { useCallback } from 'react'
+import { STORAGE_KEYS } from '@/config/storage-keys'
+import { storage } from '@/utils/storage'
+import { useResizePanel } from '../nodes/_base/hooks/use-resize-panel'
+import { SIDEBAR_DEFAULT_WIDTH, SIDEBAR_MAX_WIDTH, SIDEBAR_MIN_WIDTH } from './constants'
 
 type SidebarProps = PropsWithChildren
 
 const Sidebar: FC<SidebarProps> = ({ children }) => {
+  const { run: persistWidth } = useDebounceFn(
+    (width: number) => storage.set(STORAGE_KEYS.SKILL.SIDEBAR_WIDTH, width),
+    { wait: 200 },
+  )
+
+  const handleResize = useCallback((width: number) => {
+    persistWidth(width)
+  }, [persistWidth])
+
+  const { triggerRef, containerRef } = useResizePanel({
+    direction: 'horizontal',
+    triggerDirection: 'right',
+    minWidth: SIDEBAR_MIN_WIDTH,
+    maxWidth: SIDEBAR_MAX_WIDTH,
+    onResize: handleResize,
+  })
+
   return (
-    <aside className="flex h-full w-[320px] shrink-0 flex-col gap-px overflow-hidden rounded-[10px] border border-components-panel-border-subtle bg-components-panel-bg">
+    <aside
+      ref={containerRef}
+      style={{ width: storage.getNumber(STORAGE_KEYS.SKILL.SIDEBAR_WIDTH, SIDEBAR_DEFAULT_WIDTH) }}
+      className="relative flex h-full shrink-0 flex-col gap-px overflow-hidden rounded-[10px] border border-components-panel-border-subtle bg-components-panel-bg"
+    >
       {children}
+      <div
+        ref={triggerRef}
+        className="absolute -right-1 top-0 z-10 flex h-full w-2 cursor-col-resize items-center justify-center"
+      >
+        <div className="h-10 w-0.5 rounded-sm bg-state-base-handle transition-all hover:h-full hover:bg-state-accent-solid active:h-full active:bg-state-accent-solid" />
+      </div>
     </aside>
   )
 }
diff --git a/web/config/storage-keys.ts b/web/config/storage-keys.ts
new file mode 100644
index 0000000000..730b78da49
--- /dev/null
+++ b/web/config/storage-keys.ts
@@ -0,0 +1,5 @@
+export const STORAGE_KEYS = {
+  SKILL: {
+    SIDEBAR_WIDTH: 'skill-sidebar-width',
+  },
+} as const
diff --git a/web/utils/storage.ts b/web/utils/storage.ts
new file mode 100644
index 0000000000..e59bfb1efc
--- /dev/null
+++ b/web/utils/storage.ts
@@ -0,0 +1,117 @@
+import { isClient } from './client'
+
+type JsonValue = string | number | boolean | null | JsonValue[] | { [key: string]: JsonValue }
+
+const STORAGE_VERSION = 'v1'
+
+let _isAvailable: boolean | null = null
+
+function isLocalStorageAvailable(): boolean {
+  if (_isAvailable !== null)
+    return _isAvailable
+
+  if (!isClient) {
+    _isAvailable = false
+    return false
+  }
+
+  try {
+    const testKey = '__storage_test__'
+    localStorage.setItem(testKey, 'test')
+    localStorage.removeItem(testKey)
+    _isAvailable = true
+    return true
+  }
+  catch {
+    _isAvailable = false
+    return false
+  }
+}
+
+function versionedKey(key: string): string {
+  return `${STORAGE_VERSION}:${key}`
+}
+
+function get<T extends JsonValue>(key: string, defaultValue?: T): T | null {
+  if (!isLocalStorageAvailable())
+    return defaultValue ?? null
+
+  try {
+    const item = localStorage.getItem(versionedKey(key))
+    if (item === null)
+      return defaultValue ?? null
+
+    try {
+      return JSON.parse(item) as T
+    }
+    catch {
+      return item as T
+    }
+  }
+  catch {
+    return defaultValue ?? null
+  }
+}
+
+function set<T extends JsonValue>(key: string, value: T): void {
+  if (!isLocalStorageAvailable())
+    return
+
+  try {
+    const stringValue = typeof value === 'string' ? value : JSON.stringify(value)
+    localStorage.setItem(versionedKey(key), stringValue)
+  }
+  catch {
+    // Silent fail - localStorage may be full or disabled
+  }
+}
+
+function remove(key: string): void {
+  if (!isLocalStorageAvailable())
+    return
+
+  try {
+    localStorage.removeItem(versionedKey(key))
+  }
+  catch {
+    // Silent fail
+  }
+}
+
+function getNumber(key: string): number | null
+function getNumber(key: string, defaultValue: number): number
+function getNumber(key: string, defaultValue?: number): number | null {
+  const value = get<string | number>(key)
+  if (value === null)
+    return defaultValue ?? null
+
+  const parsed = typeof value === 'number' ? value : Number.parseFloat(value as string)
+  return Number.isNaN(parsed) ? (defaultValue ?? null) : parsed
+}
+
+function getBoolean(key: string): boolean | null
+function getBoolean(key: string, defaultValue: boolean): boolean
+function getBoolean(key: string, defaultValue?: boolean): boolean | null {
+  const value = get<string | boolean>(key)
+  if (value === null)
+    return defaultValue ?? null
+
+  if (typeof value === 'boolean')
+    return value
+
+  return value === 'true'
+}
+
+function resetCache(): void {
+  _isAvailable = null
+}
+
+export const storage = {
+  get,
+  set,
+  remove,
+  getNumber,
+  getBoolean,
+  isAvailable: isLocalStorageAvailable,
+  resetCache,
+}