diff --git a/docs/发布与更新.md b/docs/发布与更新.md
new file mode 100644
index 0000000..f3677d9
--- /dev/null
+++ b/docs/发布与更新.md
@@ -0,0 +1,32 @@
+# 发布与更新（轻量版）
+
+应用内「检查更新」按钮（顶栏右上角）走**轻量版本检查**：查询 Gitea 最新 release，与当前版本号比较，有新版则弹窗显示发布说明并提供「前往下载」。不做签名校验、不在应用内静默安装——用户下载安装包后手动运行覆盖安装。
+
+## 工作原理
+
+- 检查接口（硬编码于 `src-tauri/src/main.rs` 的 `GITEA_LATEST_RELEASE_API`）：
+  `http://gitea.xxhhcty.xyz:8080/api/v1/repos/zcdsj/tcjs/releases/latest`
+- 当前版本取自 `src-tauri/tauri.conf.json` 的 `version`（`app.package_info().version`）。
+- 比较规则：release 的 `tag_name`（去掉前导 `v`/`V`）按点分十进制与当前版本比大小。
+- 「前往下载」打开 release 资产里第一个 `.exe`/`.msi`，没有资产则打开 release 页面。
+
+## 发布一个新版本
+
+1. **改版本号**：编辑 `src-tauri/tauri.conf.json` 的 `version`（如 `0.1.0` → `0.2.0`）。建议同步 `package.json`、`src-tauri/Cargo.toml`，保持一致。
+2. **构建安装包**：`npm run tauri:build`
+   产物在 `src-tauri/target/release/bundle/`：
+   - `nsis/*.exe`（推荐发布这个）
+   - `msi/*.msi`
+3. **在 Gitea 建 release**：
+   - 仓库 `zcdsj/tcjs` → Releases → New Release。
+   - **Tag** 用 `v0.2.0`（与第 1 步版本一致；检查时会去掉前导 `v`）。
+   - 把第 2 步的 `.exe`（和/或 `.msi`）作为**附件**上传。
+   - release 正文（body）会作为「发布说明」显示在更新弹窗里，写更新内容即可。
+   - 发布（标记为最新 release）。
+4. 旧版本用户点「检查更新」→ 发现 `v0.2.0` 比本地新 → 弹窗 → 「前往下载」→ 下载安装包覆盖安装。
+
+## 备注 / 后续可选
+
+- **HTTP 站点**：当前 ureq 关闭了 TLS（Gitea 走 http）。若 Gitea 迁到 https，需要给 `src-tauri/Cargo.toml` 的 `ureq` 打开 `tls`（rustls）特性。
+- **改成静默自动更新**：若以后要"应用内下载+安装+重启"，可切换到官方 `tauri-plugin-updater`（需生成签名密钥、构建时签名、每次发布额外上传 `latest.json` 与 `.sig`）。本版刻意不做以保持轻量。
+- **API 私有仓库**：若仓库非公开，Gitea API 需要 token；当前实现按公开仓库匿名访问。
diff --git a/package.json b/package.json
index 470b57c..c4288ff 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "ceramic-radioactivity-app",
   "private": true,
-  "version": "0.1.0",
+  "version": "0.2.0",
   "type": "module",
   "scripts": {
     "dev": "vite --config ui/vite.config.ts",
diff --git a/src-tauri/Cargo.lock b/src-tauri/Cargo.lock
index 7a3d147..1bce673 100644
--- a/src-tauri/Cargo.lock
+++ b/src-tauri/Cargo.lock
@@ -285,7 +285,7 @@ dependencies = [
 
 [[package]]
 name = "ceramic-radioactivity-tauri"
-version = "0.1.0"
+version = "0.2.0"
 dependencies = [
  "ceramic-radioactivity",
  "rusqlite",
@@ -295,6 +295,7 @@ dependencies = [
  "tauri",
  "tauri-build",
  "tauri-plugin-dialog",
+ "ureq",
 ]
 
 [[package]]
@@ -3763,6 +3764,31 @@ version = "0.2.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ebc1c04c71510c7f702b52b7c350734c9ff1295c464a03335b00bb84fc54f853"
 
+[[package]]
+name = "ureq"
+version = "3.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dea7109cdcd5864d4eeb1b58a1648dc9bf520360d7af16ec26d0a9354bafcfc0"
+dependencies = [
+ "base64 0.22.1",
+ "log",
+ "percent-encoding",
+ "ureq-proto",
+ "utf8-zero",
+]
+
+[[package]]
+name = "ureq-proto"
+version = "0.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e994ba84b0bd1b1b0cf92878b7ef898a5c1760108fe7b6010327e274917a808c"
+dependencies = [
+ "base64 0.22.1",
+ "http",
+ "httparse",
+ "log",
+]
+
 [[package]]
 name = "url"
 version = "2.5.8"
@@ -3794,6 +3820,12 @@ version = "0.7.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "09cc8ee72d2a9becf2f2febe0205bbed8fc6615b7cb429ad062dc7b7ddd036a9"
 
+[[package]]
+name = "utf8-zero"
+version = "0.8.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b8c0a043c9540bae7c578c88f91dda8bd82e59ae27c21baca69c8b191aaf5a6e"
+
 [[package]]
 name = "utf8_iter"
 version = "1.0.4"
diff --git a/src-tauri/Cargo.toml b/src-tauri/Cargo.toml
index 41abf88..485a55e 100644
--- a/src-tauri/Cargo.toml
+++ b/src-tauri/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "ceramic-radioactivity-tauri"
-version = "0.1.0"
+version = "0.2.0"
 edition = "2021"
 
 [build-dependencies]
@@ -14,3 +14,4 @@ serde = { version = "1", features = ["derive"] }
 serde_json = "1.0.150"
 tauri = { version = "2", features = [] }
 tauri-plugin-dialog = "2.7.1"
+ureq = { version = "3.3.0", default-features = false }
diff --git a/src-tauri/src/main.rs b/src-tauri/src/main.rs
index 47e42aa..87286fb 100644
--- a/src-tauri/src/main.rs
+++ b/src-tauri/src/main.rs
@@ -78,6 +78,110 @@ fn export_excel(app: tauri::AppHandle, db: State<Db>, id: i64) -> Result<Option<
     excel::write_to_path(&path, &detail).map(Some)
 }
 
+/// Gitea「最新 release」API。如迁移到 https 站点，需为 ureq 启用 tls 特性。
+const GITEA_LATEST_RELEASE_API: &str =
+    "http://gitea.xxhhcty.xyz:8080/api/v1/repos/zcdsj/tcjs/releases/latest";
+
+#[derive(serde::Serialize)]
+struct UpdateInfo {
+    current_version: String,
+    latest_version: String,
+    has_update: bool,
+    notes: String,
+    release_url: String,
+    download_url: Option<String>,
+}
+
+/// 查询 Gitea 最新 release，与当前版本比较（轻量版本检查，不做签名校验）。
+#[tauri::command]
+fn check_update(app: tauri::AppHandle) -> Result<UpdateInfo, String> {
+    let current = app.package_info().version.to_string();
+
+    let mut resp = match ureq::get(GITEA_LATEST_RELEASE_API).call() {
+        Ok(resp) => resp,
+        // 仓库尚无任何发布：视为已是最新，而非报错。
+        Err(ureq::Error::StatusCode(404)) => return Ok(up_to_date(current)),
+        Err(ureq::Error::StatusCode(code)) => return Err(format!("Gitea 返回状态 {code}")),
+        Err(e) => return Err(format!("请求 Gitea 失败：{e}")),
+    };
+    match resp.status().as_u16() {
+        200 => {}
+        404 => return Ok(up_to_date(current)),
+        code => return Err(format!("Gitea 返回状态 {code}")),
+    }
+    let body = resp.body_mut().read_to_string().map_err(|e| e.to_string())?;
+    let json: serde_json::Value = serde_json::from_str(&body).map_err(|e| e.to_string())?;
+
+    let latest_version = json["tag_name"]
+        .as_str()
+        .unwrap_or_default()
+        .trim_start_matches(['v', 'V'])
+        .to_string();
+    let notes = json["body"].as_str().unwrap_or_default().to_string();
+    let release_url = json["html_url"].as_str().unwrap_or_default().to_string();
+    let download_url = json["assets"].as_array().and_then(|assets| {
+        assets.iter().find_map(|asset| {
+            let name = asset["name"].as_str().unwrap_or_default().to_ascii_lowercase();
+            if name.ends_with(".exe") || name.ends_with(".msi") {
+                asset["browser_download_url"].as_str().map(str::to_string)
+            } else {
+                None
+            }
+        })
+    });
+
+    Ok(UpdateInfo {
+        has_update: is_newer(&latest_version, &current),
+        current_version: current,
+        latest_version,
+        notes,
+        release_url,
+        download_url,
+    })
+}
+
+/// 构造「已是最新」结果（无更新）。
+fn up_to_date(current: String) -> UpdateInfo {
+    UpdateInfo {
+        latest_version: current.clone(),
+        current_version: current,
+        has_update: false,
+        notes: String::new(),
+        release_url: String::new(),
+        download_url: None,
+    }
+}
+
+/// 用默认浏览器打开 URL（跳转到 release 下载页 / 安装包）。
+#[tauri::command]
+fn open_external(url: String) -> Result<(), String> {
+    let mut command = std::process::Command::new("cmd");
+    command.args(["/C", "start", "", &url]);
+    #[cfg(windows)]
+    {
+        use std::os::windows::process::CommandExt;
+        command.creation_flags(0x0800_0000); // CREATE_NO_WINDOW，避免闪现控制台
+    }
+    command.spawn().map_err(|e| e.to_string())?;
+    Ok(())
+}
+
+/// 比较点分十进制版本：a 是否比 b 新（缺位按 0）。
+fn is_newer(a: &str, b: &str) -> bool {
+    let parse = |s: &str| -> Vec<u64> {
+        s.split('.').map(|p| p.trim().parse().unwrap_or(0)).collect()
+    };
+    let (va, vb) = (parse(a), parse(b));
+    for i in 0..va.len().max(vb.len()) {
+        let x = va.get(i).copied().unwrap_or(0);
+        let y = vb.get(i).copied().unwrap_or(0);
+        if x != y {
+            return x > y;
+        }
+    }
+    false
+}
+
 fn main() {
     tauri::Builder::default()
         .plugin(tauri_plugin_dialog::init())
@@ -95,8 +199,26 @@ fn main() {
             list_records,
             get_record,
             delete_record,
-            export_excel
+            export_excel,
+            check_update,
+            open_external
         ])
         .run(tauri::generate_context!())
         .expect("failed to run Tauri application");
 }
+
+#[cfg(test)]
+mod tests {
+    use super::is_newer;
+
+    #[test]
+    fn version_comparison() {
+        assert!(is_newer("0.2.0", "0.1.0"));
+        assert!(is_newer("1.0.0", "0.9.9"));
+        assert!(is_newer("0.1.1", "0.1.0"));
+        assert!(is_newer("0.2", "0.1.5")); // 缺位按 0
+        assert!(!is_newer("0.1.0", "0.1.0"));
+        assert!(!is_newer("0.1.0", "0.2.0"));
+        assert!(!is_newer("", "0.1.0"));
+    }
+}
diff --git a/src-tauri/tauri.conf.json b/src-tauri/tauri.conf.json
index 9fd96b6..eeb3d7f 100644
--- a/src-tauri/tauri.conf.json
+++ b/src-tauri/tauri.conf.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://schema.tauri.app/config/2",
   "productName": "Building Material Radioactivity",
-  "version": "0.1.0",
+  "version": "0.2.0",
   "identifier": "com.tcjs.ceramic-radioactivity",
   "build": {
     "beforeDevCommand": "npm run dev",
diff --git a/ui/src/App.tsx b/ui/src/App.tsx
index 90e8082..29c3d88 100644
--- a/ui/src/App.tsx
+++ b/ui/src/App.tsx
@@ -3,6 +3,7 @@ import { App as AntApp, ConfigProvider, Tabs } from "antd";
 import zhCN from "antd/locale/zh_CN";
 import { CalculatorPanel } from "./CalculatorPanel";
 import { HistoryTab } from "./HistoryTab";
+import { UpdateButton } from "./UpdateButton";
 import type { SampleInput } from "./types";
 
 function Brand() {
@@ -47,7 +48,7 @@ function App() {
             activeKey={activeTab}
             onChange={setActiveTab}
             className="main-tabs"
-            tabBarExtraContent={{ left: <Brand /> }}
+            tabBarExtraContent={{ left: <Brand />, right: <UpdateButton /> }}
             items={[
               {
                 key: "calc",
diff --git a/ui/src/UpdateButton.tsx b/ui/src/UpdateButton.tsx
new file mode 100644
index 0000000..7b8ea62
--- /dev/null
+++ b/ui/src/UpdateButton.tsx
@@ -0,0 +1,51 @@
+import { useState } from "react";
+import { invoke } from "@tauri-apps/api/core";
+import { App, Button } from "antd";
+import type { UpdateInfo } from "./types";
+
+/** 手动「检查更新」：查询 Gitea 最新 release，有新版则提示并可跳转下载。 */
+function UpdateButton() {
+  const { message, modal } = App.useApp();
+  const [loading, setLoading] = useState(false);
+
+  const check = async () => {
+    setLoading(true);
+    try {
+      const info = await invoke<UpdateInfo>("check_update");
+      if (info.has_update) {
+        modal.confirm({
+          title: `发现新版本 v${info.latest_version}`,
+          width: 540,
+          okText: "前往下载",
+          cancelText: "稍后",
+          content: (
+            <div>
+              <p className="update-versions">
+                当前 v{info.current_version} → 最新 <strong>v{info.latest_version}</strong>
+              </p>
+              {info.notes ? <pre className="update-notes">{info.notes}</pre> : null}
+            </div>
+          ),
+          onOk: () =>
+            invoke("open_external", { url: info.download_url || info.release_url }).catch((err) =>
+              message.error(`打开下载页失败：${String(err)}`)
+            )
+        });
+      } else {
+        message.success(`已是最新版本 v${info.current_version}`);
+      }
+    } catch (err) {
+      message.error(`检查更新失败：${String(err)}`);
+    } finally {
+      setLoading(false);
+    }
+  };
+
+  return (
+    <Button size="small" className="update-btn" loading={loading} onClick={() => void check()}>
+      检查更新
+    </Button>
+  );
+}
+
+export { UpdateButton };
diff --git a/ui/src/styles.css b/ui/src/styles.css
index 07b206d..449a19b 100644
--- a/ui/src/styles.css
+++ b/ui/src/styles.css
@@ -83,6 +83,39 @@ body {
   white-space: nowrap;
 }
 
+/* 顶栏右侧「检查更新」按钮：navy 底上的浅色描边按钮 */
+.update-btn {
+  background: transparent;
+  border-color: rgba(255, 255, 255, 0.4);
+  color: #e8edf5;
+}
+
+.update-btn:hover,
+.update-btn:focus {
+  background: transparent !important;
+  border-color: #f2b50c !important;
+  color: #f2b50c !important;
+}
+
+.update-versions {
+  margin: 4px 0 10px;
+  color: #69727c;
+}
+
+.update-notes {
+  max-height: 240px;
+  overflow: auto;
+  white-space: pre-wrap;
+  word-break: break-word;
+  margin: 0;
+  padding: 10px 12px;
+  background: #f6f8fa;
+  border: 1px solid #e9edf1;
+  border-radius: 8px;
+  font-size: 13px;
+  line-height: 1.5;
+}
+
 .results-toolbar {
   display: flex;
   gap: 8px;
diff --git a/ui/src/types.ts b/ui/src/types.ts
index e5f026b..5098748 100644
--- a/ui/src/types.ts
+++ b/ui/src/types.ts
@@ -109,6 +109,15 @@ export type RecordDetail = {
   result: CalculationResult;
 };
 
+export type UpdateInfo = {
+  current_version: string;
+  latest_version: string;
+  has_update: boolean;
+  notes: string;
+  release_url: string;
+  download_url: string | null;
+};
+
 export type RecordFilter = {
   sample_id: string | null;
   material_type: MaterialType | null;