diff --git a/.github/workflows/deployment-gate.yml b/.github/workflows/deployment-gate.yml
new file mode 100644
index 0000000..c500d7e
--- /dev/null
+++ b/.github/workflows/deployment-gate.yml
@@ -0,0 +1,69 @@
+name: Deployment Gate
+
+on:
+  workflow_dispatch:
+    inputs:
+      target:
+        description: staging 或 production
+        required: true
+        default: staging
+        type: choice
+        options:
+          - staging
+          - production
+      base_url:
+        description: TypeTwo Server HTTPS URL
+        required: true
+        type: string
+      expected_environment:
+        description: /health environment 預期值
+        required: true
+        default: production
+        type: string
+      skip_smoke:
+        description: 只檢查 /health，不執行會寫入資料的 smoke
+        required: true
+        default: false
+        type: boolean
+
+permissions:
+  contents: read
+
+env:
+  FORCE_JAVASCRIPT_ACTIONS_TO_NODE24: true
+
+jobs:
+  deployment-gate:
+    runs-on: windows-latest
+    timeout-minutes: 20
+    environment: ${{ inputs.target }}
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Run deployment gate
+        shell: powershell
+        env:
+          ADMIN_EMAIL: ${{ secrets.TYPETWO_ADMIN_EMAIL }}
+          ADMIN_PASSWORD: ${{ secrets.TYPETWO_ADMIN_PASSWORD }}
+        run: |
+          $args = @(
+            '-BaseUrl', '${{ inputs.base_url }}',
+            '-ExpectedEnvironment', '${{ inputs.expected_environment }}',
+            '-EvidencePath', 'deployment-evidence-${{ inputs.target }}.json'
+          )
+
+          if ('${{ inputs.skip_smoke }}' -eq 'true') {
+            $args += '-SkipSmoke'
+          }
+
+          .\scripts\test_typetwo_deployment_gate.ps1 @args
+
+      - name: Upload deployment evidence
+        uses: actions/upload-artifact@v4
+        if: always()
+        with:
+          name: deployment-evidence-${{ inputs.target }}
+          path: deployment-evidence-${{ inputs.target }}.json
+          if-no-files-found: warn
diff --git a/COMPLETION_AUDIT.md b/COMPLETION_AUDIT.md
index 79ad503..57609c6 100644
--- a/COMPLETION_AUDIT.md
+++ b/COMPLETION_AUDIT.md
@@ -37,6 +37,9 @@ M0、M2、M3、M4 與 M5 的程式、文件、測試與本機 production-like 
 - `master` CI run `26617148862`：`backend-quality` 與 `windows-quality` 皆通過。
 - GitHub Release `v1.0.18`：release workflow run `26617247786` 通過，已附加 `setup_typetwo.exe`、`setup_typetwo.exe.sha256`、`typetwo-glossary-api-v1.0.18.tar`、`typetwo-glossary-api-v1.0.18.tar.sha256`。
 - GitHub Release `v1.0.18` checksum：release assets 已下載後重新計算，installer 與 backend image checksum 皆吻合。
+- 已新增 `scripts/test_typetwo_deployment_gate.ps1`，可對 staging/production URL 執行 `/health`、smoke、備份還原驗證並輸出 evidence JSON。
+- 已新增 GitHub Actions `Deployment Gate` workflow，設定 environment secrets 後可手動對 staging/production URL 產出 deployment evidence artifact。
+- 本機 Docker 已實測 `test_typetwo_deployment_gate.ps1 -AllowHttp -ExpectedEnvironment development`，`health` 與 `smoke` 均通過，cleanup 成功；production/staging 仍需真實 HTTPS URL 重跑。
 
 ## 外部環境待驗證
 
@@ -45,6 +48,7 @@ M0、M2、M3、M4 與 M5 的程式、文件、測試與本機 production-like 
 | 正式 HTTPS domain | 需要真實 DNS、TLS 憑證與可從公司外連線的主機 | `Invoke-RestMethod https://<domain>/health` 回傳 `ok=true`、`db=ok`、`environment=production` |
 | staging smoke | 需要 staging domain 與 staging DB | 對 staging URL 執行 `.\scripts\smoke_typetwo_glossary_api.ps1 -BaseUrl https://<staging-domain>` |
 | production smoke | 需要 production domain 與 production 帳號策略 | 對 production URL 執行 smoke，確認 cleanup 後沒有測試詞彙與可登入測試帳號 |
+| staging/production evidence | 已有腳本與 workflow，仍需要真實 URL 與 admin secrets | 執行 `test_typetwo_deployment_gate.ps1` 或 GitHub Actions `Deployment Gate` |
 | GitHub Actions 綠燈 | 已在 PR 與 `master` 驗證通過 | `CI / backend-quality` 與 `CI / windows-quality` 皆通過 |
 | Release artifact 可下載 | 已在 GitHub Release `v1.0.18` 驗證通過 | Release 內有 `setup_typetwo.exe`、`setup_typetwo.exe.sha256`、`typetwo-glossary-api-v1.0.18.tar`、`typetwo-glossary-api-v1.0.18.tar.sha256` |
 | production 備份還原演練 | 需要 production DB 備份檔與非 production 還原環境 | 用 `.\scripts\verify_typetwo_postgres_backup.ps1 -BackupZip <production-backup.zip>` 驗證成功 |
@@ -60,3 +64,12 @@ M0、M2、M3、M4 與 M5 的程式、文件、測試與本機 production-like 
 5. GitHub Release event 產出 installer、backend image tar 與各自 checksum，並附加到 GitHub Release。
 6. production 備份已還原到非 production volume 驗證。
 7. rollback runbook 至少演練一次並記錄結果。
+
+## 仍需提供的外部設定
+
+repo 目前沒有部署 secrets、environment variables、遠端主機或 DNS 設定。若要讓 GitHub Actions `Deployment Gate` 直接完成 staging/production evidence，需先在 GitHub environment `staging` 與 `production` 設定：
+
+- `TYPETWO_ADMIN_EMAIL`
+- `TYPETWO_ADMIN_PASSWORD`
+
+並準備可從 GitHub runner 連線的 HTTPS URL，例如 `https://typetwo-glossary.company.com`。
diff --git a/DEPLOYMENT.md b/DEPLOYMENT.md
index 35db4b0..e12f0ed 100644
--- a/DEPLOYMENT.md
+++ b/DEPLOYMENT.md
@@ -51,6 +51,24 @@ docker compose -f docker-compose.yml -f docker-compose.prod.yml up -d --build
 
 smoke script 會建立臨時 approved 詞彙、臨時 user、pending 建議詞，驗證 approve 後可進 approved 詞彙包，最後刪除 smoke 詞彙、停用 smoke user，並確認既有 token 已失效。
 
+也可以用 deployment gate 統一產出證據檔：
+
+```powershell
+.\scripts\test_typetwo_deployment_gate.ps1 `
+  -BaseUrl "https://staging.example.com" `
+  -ExpectedEnvironment "production" `
+  -AdminEmail $env:ADMIN_EMAIL `
+  -AdminPassword $env:ADMIN_PASSWORD `
+  -EvidencePath ".\evidence\staging-deployment-gate.json"
+```
+
+GitHub Actions 也提供手動 workflow `Deployment Gate`。使用前需在對應 environment 設定 secrets：
+
+- `TYPETWO_ADMIN_EMAIL`
+- `TYPETWO_ADMIN_PASSWORD`
+
+執行 workflow 時輸入 staging 或 production URL；workflow 會上傳 `deployment-evidence-<target>.json` artifact。
+
 ## Production 部署
 
 1. 備份 production PostgreSQL。
@@ -79,6 +97,18 @@ docker compose -f docker-compose.yml -f docker-compose.prod.yml up -d
   -AdminPassword $env:ADMIN_PASSWORD
 ```
 
+建議正式驗收改用 deployment gate，同時輸出 evidence：
+
+```powershell
+.\scripts\test_typetwo_deployment_gate.ps1 `
+  -BaseUrl $env:PUBLIC_BASE_URL `
+  -ExpectedEnvironment "production" `
+  -AdminEmail $env:ADMIN_EMAIL `
+  -AdminPassword $env:ADMIN_PASSWORD `
+  -BackupZip ".\backups\typetwo_<timestamp>.sql.zip" `
+  -EvidencePath ".\evidence\production-deployment-gate.json"
+```
+
 ## 備份與還原驗證
 
 建立備份：
diff --git a/RELEASE_CHECKLIST.md b/RELEASE_CHECKLIST.md
index 0ce83b8..27d76ea 100644
--- a/RELEASE_CHECKLIST.md
+++ b/RELEASE_CHECKLIST.md
@@ -52,6 +52,7 @@
 - staging 備份已用 `verify_typetwo_postgres_backup.ps1` 還原到臨時 volume 驗證。
 - Alembic migration 已在 staging 成功升級到 head。
 - staging smoke 通過。
+- `test_typetwo_deployment_gate.ps1` 或 GitHub Actions `Deployment Gate` 已產出 staging evidence JSON。
 - Flutter App 可連 staging TypeTwo Server 並完成登入、同步、pending review、匯入預覽。
 
 ## Production
@@ -62,6 +63,7 @@
 - Alembic migration 已執行。
 - service 已啟動，`/health` 為 `ok=true`、`db=ok`、`environment=production`。
 - production smoke 通過且 cleanup 驗證通過。
+- `test_typetwo_deployment_gate.ps1` 或 GitHub Actions `Deployment Gate` 已產出 production evidence JSON。
 - rollback owner 與 rollback artifact 已確認。
 
 ## Release notes
diff --git a/plan-20260526.md b/plan-20260526.md
index c24db53..bee5131 100644
--- a/plan-20260526.md
+++ b/plan-20260526.md
@@ -565,6 +565,14 @@ docker compose -f docker-compose.yml -f docker-compose.prod.yml config
 - 已建立 GitHub Release `v1.0.18`，release workflow run `26617247786` 已通過，並成功附加 installer、backend image tar 與各自 SHA256。
 - 已下載 GitHub Release `v1.0.18` assets 並重新計算 SHA256，確認 release 內附 checksum 皆吻合。
 
+### 2026-05-29：部署 evidence gate 增量
+
+- 已新增 `scripts/test_typetwo_deployment_gate.ps1`，可對 staging/production URL 統一執行 `/health`、smoke、備份還原驗證，並輸出 JSON evidence。
+- 已新增 GitHub Actions `Deployment Gate` workflow，可手動輸入 staging/production URL，使用 environment secrets 執行遠端 smoke 並上傳 evidence artifact。
+- `DEPLOYMENT.md`、`RELEASE_CHECKLIST.md` 與 `COMPLETION_AUDIT.md` 已補上 deployment gate 使用方式與完成條件。
+- 已用本機 Docker 實測 deployment gate，`health` 與 `smoke` 皆通過，並確認 cleanup 成功。
+- repo 目前沒有 staging/production 主機、DNS、GitHub Secrets 或 Variables；最後外部 gate 仍需真實 HTTPS URL 與 admin credentials 才能執行。
+
 ## 下一步建議
 
 下一輪優先補齊外部環境證據：
diff --git a/scripts/test_typetwo_deployment_gate.ps1 b/scripts/test_typetwo_deployment_gate.ps1
new file mode 100644
index 0000000..b4492b6
--- /dev/null
+++ b/scripts/test_typetwo_deployment_gate.ps1
@@ -0,0 +1,149 @@
+param(
+  [Parameter(Mandatory = $true)][string]$BaseUrl,
+  [string]$AdminEmail = $env:ADMIN_EMAIL,
+  [string]$AdminPassword = $env:ADMIN_PASSWORD,
+  [string]$ExpectedEnvironment = "",
+  [string]$BackupZip = "",
+  [string]$EvidencePath = ".\deployment-evidence.json",
+  [switch]$AllowHttp,
+  [switch]$SkipSmoke,
+  [switch]$SkipBackupVerify
+)
+
+$ErrorActionPreference = "Stop"
+
+function Add-Step {
+  param(
+    [System.Collections.Generic.List[object]]$Steps,
+    [Parameter(Mandatory = $true)][string]$Name,
+    [Parameter(Mandatory = $true)][string]$Status,
+    [object]$Details = $null
+  )
+
+  $Steps.Add([pscustomobject]@{
+    name = $Name
+    status = $Status
+    details = $Details
+    checkedAt = (Get-Date).ToUniversalTime().ToString("o")
+  })
+}
+
+function Assert-Url {
+  param([string]$Value)
+
+  try {
+    $uri = [Uri]$Value
+  } catch {
+    throw "BaseUrl 必須是有效 URL：$Value"
+  }
+
+  if (-not $AllowHttp -and $uri.Scheme -ne "https") {
+    throw "BaseUrl 必須使用 https://；本機或臨時測試才可加 -AllowHttp"
+  }
+
+  if ($uri.AbsolutePath -ne "/") {
+    return $Value.TrimEnd("/")
+  }
+
+  return "$($uri.Scheme)://$($uri.Authority)"
+}
+
+function Wait-TypeTwoHealth {
+  param(
+    [Parameter(Mandatory = $true)][string]$Url,
+    [int]$TimeoutSeconds = 90
+  )
+
+  $deadline = (Get-Date).AddSeconds($TimeoutSeconds)
+  $lastError = $null
+
+  do {
+    try {
+      $body = Invoke-RestMethod -Method Get -Uri "$Url/health"
+      if ($body.ok -eq $true -and $body.db -eq "ok") {
+        return $body
+      }
+      $lastError = "/health 回傳異常：$($body | ConvertTo-Json -Compress -Depth 8)"
+    } catch {
+      $lastError = $_.Exception.Message
+    }
+
+    Start-Sleep -Seconds 2
+  } while ((Get-Date) -lt $deadline)
+
+  throw "API healthcheck 未在期限內通過：$lastError"
+}
+
+$normalizedBaseUrl = Assert-Url -Value $BaseUrl
+$steps = New-Object "System.Collections.Generic.List[object]"
+$summary = [ordered]@{
+  ok = $false
+  baseUrl = $normalizedBaseUrl
+  expectedEnvironment = $ExpectedEnvironment
+  startedAt = (Get-Date).ToUniversalTime().ToString("o")
+  completedAt = $null
+  steps = $steps
+}
+
+try {
+  $health = Wait-TypeTwoHealth -Url $normalizedBaseUrl
+
+  if (-not [string]::IsNullOrWhiteSpace($ExpectedEnvironment) -and
+      $health.environment -ne $ExpectedEnvironment) {
+    throw "/health environment 不符合預期：expected=$ExpectedEnvironment actual=$($health.environment)"
+  }
+
+  Add-Step -Steps $steps -Name "health" -Status "passed" -Details $health
+
+  if ($SkipSmoke) {
+    Add-Step -Steps $steps -Name "smoke" -Status "skipped" -Details "已使用 -SkipSmoke"
+  } else {
+    if ([string]::IsNullOrWhiteSpace($AdminEmail) -or [string]::IsNullOrWhiteSpace($AdminPassword)) {
+      throw "執行 smoke 需要 AdminEmail/AdminPassword，或使用 -SkipSmoke"
+    }
+
+    $smokeJson = & "$PSScriptRoot\smoke_typetwo_glossary_api.ps1" `
+      -BaseUrl $normalizedBaseUrl `
+      -AdminEmail $AdminEmail `
+      -AdminPassword $AdminPassword
+    if ($LASTEXITCODE -ne 0) {
+      throw "smoke script 失敗"
+    }
+
+    $smokeResult = $smokeJson | ConvertFrom-Json
+    if ($smokeResult.ok -ne $true) {
+      throw "smoke result 不符合預期：$($smokeResult | ConvertTo-Json -Compress -Depth 8)"
+    }
+
+    Add-Step -Steps $steps -Name "smoke" -Status "passed" -Details $smokeResult
+  }
+
+  if ($SkipBackupVerify) {
+    Add-Step -Steps $steps -Name "backup-restore" -Status "skipped" -Details "已使用 -SkipBackupVerify"
+  } elseif ([string]::IsNullOrWhiteSpace($BackupZip)) {
+    Add-Step -Steps $steps -Name "backup-restore" -Status "skipped" -Details "未提供 BackupZip"
+  } else {
+    & "$PSScriptRoot\verify_typetwo_postgres_backup.ps1" -BackupZip $BackupZip
+    if ($LASTEXITCODE -ne 0) {
+      throw "備份還原驗證失敗"
+    }
+
+    Add-Step -Steps $steps -Name "backup-restore" -Status "passed" -Details @{
+      backupZip = (Resolve-Path -LiteralPath $BackupZip).Path
+    }
+  }
+
+  $summary.ok = $true
+} catch {
+  Add-Step -Steps $steps -Name "deployment-gate" -Status "failed" -Details $_.Exception.Message
+  throw
+} finally {
+  $summary.completedAt = (Get-Date).ToUniversalTime().ToString("o")
+  $evidenceDir = Split-Path -Parent $EvidencePath
+  if (-not [string]::IsNullOrWhiteSpace($evidenceDir)) {
+    New-Item -ItemType Directory -Force -Path $evidenceDir | Out-Null
+  }
+  [pscustomobject]$summary | ConvertTo-Json -Depth 12 |
+    Set-Content -Encoding utf8 -Path $EvidencePath
+  Write-Output "部署 gate 證據已寫入：$EvidencePath"
+}