diff --git a/src/components/sp-web-decoration/preview-locale-url.test.mjs b/src/components/sp-web-decoration/preview-locale-url.test.mjs
new file mode 100644
index 0000000..de66f5b
--- /dev/null
+++ b/src/components/sp-web-decoration/preview-locale-url.test.mjs
@@ -0,0 +1,114 @@
+import assert from 'node:assert/strict'
+import { readFileSync } from 'node:fs'
+import path from 'node:path'
+import test from 'node:test'
+
+const root = process.cwd()
+const read = (filePath) => readFileSync(path.resolve(root, filePath), 'utf8')
+
+function loadDecorationMessenger() {
+  const pageTypesSource = read('src/components/sp-web-decoration/utils/pageTypes.js').replace(
+    /export\s+/g,
+    ''
+  )
+  const postMessageSource = read('src/components/sp-web-decoration/utils/postMessage.js')
+    .replace(/import\s+\{[^}]+\}\s+from\s+'\.\/pageTypes'\n/, '')
+    .replace(/export\s+default\s+\{[\s\S]*$/, '')
+    .replace(/export\s+/g, '')
+
+  return new Function(
+    `${pageTypesSource}\n${postMessageSource}\nreturn { createDecorationMessenger }`
+  )()
+}
+
+function setupWindow(lang) {
+  globalThis.window = {
+    location: { href: 'https://admin.example.test/admin/decoration' },
+    localStorage: {
+      getItem(key) {
+        return key === 'lang' ? lang : null
+      }
+    },
+    addEventListener() {},
+    removeEventListener() {}
+  }
+}
+
+test.afterEach(() => {
+  delete globalThis.window
+})
+
+function previewUrlFor(lang, options = {}) {
+  setupWindow(lang)
+  const { createDecorationMessenger } = loadDecorationMessenger()
+  const messenger = createDecorationMessenger('https://shop.example.test/store?foo=bar')
+  return new URL(
+    messenger.getPreviewUrl({
+      pageType: 'home',
+      templateId: undefined,
+      ...options
+    })
+  )
+}
+
+test('preview url uses /en prefix for English admin locale', () => {
+  const url = previewUrlFor('en')
+
+  assert.equal(url.pathname, '/en')
+})
+
+test('preview url uses /ar prefix for Arabic admin locale', () => {
+  const url = previewUrlFor('ar')
+
+  assert.equal(url.pathname, '/ar')
+})
+
+test('preview url keeps root path for zhcn admin locale', () => {
+  const url = previewUrlFor('zhcn')
+
+  assert.equal(url.pathname, '/')
+})
+
+test('preview url preserves locale prefix for custom page', () => {
+  const url = previewUrlFor('en', { pageType: 'custom', templateId: 'abc' })
+
+  assert.equal(url.pathname, '/en/custom/abc')
+})
+
+test('preview url preserves query params', () => {
+  const url = previewUrlFor('en', { pageType: 'product_list' })
+
+  assert.equal(url.pathname, '/en/collections/all')
+  assert.equal(url.searchParams.get('foo'), 'bar')
+  assert.equal(url.searchParams.get('designMode'), '1')
+  assert.equal(url.searchParams.get('pageType'), 'product_list')
+  assert.equal(url.searchParams.get('pageId'), 'product_list')
+})
+
+test('locale path does not change postMessage payloads or target origin', () => {
+  setupWindow('en')
+  const { createDecorationMessenger } = loadDecorationMessenger()
+  const messenger = createDecorationMessenger('https://shop.example.test/base')
+  const calls = []
+  const iframeWindow = {
+    postMessage(message, targetOrigin) {
+      calls.push({ message, targetOrigin })
+    }
+  }
+  const initPayload = { sections: [{ id: 'hero' }] }
+  const updatePayload = { selected: { sectionId: 'hero' } }
+
+  messenger.sendInit(iframeWindow, initPayload)
+  messenger.sendUpdate(iframeWindow, updatePayload)
+
+  assert.deepEqual(calls, [
+    {
+      message: { type: 'DECORATION_INIT', payload: initPayload },
+      targetOrigin: 'https://shop.example.test'
+    },
+    {
+      message: { type: 'DECORATION_UPDATE', payload: updatePayload },
+      targetOrigin: 'https://shop.example.test'
+    }
+  ])
+})
diff --git a/src/components/sp-web-decoration/utils/postMessage.js b/src/components/sp-web-decoration/utils/postMessage.js
index f178ec3..af6853a 100644
--- a/src/components/sp-web-decoration/utils/postMessage.js
+++ b/src/components/sp-web-decoration/utils/postMessage.js
@@ -1,5 +1,33 @@
 import { normalizeDecorationPageType, resolveDecorationPreviewPath } from './pageTypes'
 
+const ADMIN_TO_WEB_LOCALE_PREFIX = {
+  en: '/en',
+  ar: '/ar',
+  zhcn: '',
+  zhtw: ''
+}
+
+function getCurrentAdminLang() {
+  if (typeof window === 'undefined') return ''
+  try {
+    return String(window.localStorage?.getItem('lang') || '').toLowerCase()
+  } catch {
+    return ''
+  }
+}
+
+function resolveWebLocalePrefix(lang = getCurrentAdminLang()) {
+  return ADMIN_TO_WEB_LOCALE_PREFIX[lang] || ''
+}
+
+function joinPreviewPath(localePrefix, routePath) {
+  const prefix = String(localePrefix || '').replace(/\/+$/, '')
+  const path = String(routePath || '/')
+  if (!prefix) return path || '/'
+  const suffix = path.replace(/^\/+/, '')
+  return suffix ? `${prefix}/${suffix}` : prefix
+}
+
 function resolvePreviewWebsiteOrigin(websiteUrl) {
   if (!websiteUrl) return ''
   try {
@@ -66,7 +94,8 @@ export function createDecorationMessenger(websiteUrl) {
       if (!base.pathname || base.pathname === '') {
         base.pathname = '/'
       }
-      base.pathname = resolveDecorationPreviewPath(normalizedPageType, pageId)
+      const routePath = resolveDecorationPreviewPath(normalizedPageType, pageId)
+      base.pathname = joinPreviewPath(resolveWebLocalePrefix(), routePath)
       base.searchParams.set('designMode', '1')
       base.searchParams.set('pageType', normalizedPageType)
       base.searchParams.set('pageId', String(pageId))
@@ -78,7 +107,8 @@ export function createDecorationMessenger(websiteUrl) {
         pageType: String(normalizedPageType),
         pageId: String(pageId)
       })
-      const path = resolveDecorationPreviewPath(normalizedPageType, pageId).replace(/\/$/, '')
+      const routePath = resolveDecorationPreviewPath(normalizedPageType, pageId)
+      const path = joinPreviewPath(resolveWebLocalePrefix(), routePath).replace(/\/$/, '')
       return `${originOnly}${path}/?${qs.toString()}`
     }
   }