diff --git a/src/app/repo/scripts.test.ts b/src/app/repo/scripts.test.ts
new file mode 100644
index 000000000..54f040456
--- /dev/null
+++ b/src/app/repo/scripts.test.ts
@@ -0,0 +1,154 @@
+import { describe, it, expect, beforeEach } from "vitest";
+import {
+  ScriptDAO,
+  type Script,
+  SCRIPT_TYPE_NORMAL,
+  SCRIPT_STATUS_ENABLE,
+  SCRIPT_RUN_STATUS_COMPLETE,
+} from "./scripts";
+
+const baseMeta = {
+  name: ["测试脚本"],
+  namespace: ["test-namespace"],
+  version: ["1.0.0"],
+  author: ["测试作者"],
+  copyright: ["(c) 测试"],
+  grant: ["GM_xmlhttpRequest"],
+  match: ["https://example.com/*"],
+  license: ["MIT"],
+};
+
+const makeBaseScript = (overrides: Partial<Script>): Script => ({
+  uuid: "uuid-base",
+  name: "测试脚本",
+  namespace: "test-namespace",
+  author: "测试作者",
+  type: SCRIPT_TYPE_NORMAL,
+  status: SCRIPT_STATUS_ENABLE,
+  sort: 0,
+  runStatus: SCRIPT_RUN_STATUS_COMPLETE,
+  createtime: Date.now(),
+  updatetime: Date.now(),
+  checktime: Date.now(),
+  origin: "https://example.com/script.user.js",
+  metadata: { ...baseMeta },
+  ...overrides,
+});
+
+describe("ScriptDAO.searchExistingScript", () => {
+  let dao: ScriptDAO;
+
+  beforeEach(() => {
+    dao = new ScriptDAO();
+  });
+
+  it("应能在 scriptcat 场景下匹配到已存在脚本（忽略脚本名差异并校验作者/授权/匹配等信息）", async () => {
+    const existing = makeBaseScript({
+      uuid: "sc-1",
+      origin: "https://scriptcat.org/scripts/code/1234/old-name.js",
+    });
+    await dao.save(existing);
+
+    const target: Script = makeBaseScript({
+      uuid: "target-1",
+      origin: "https://scriptcat.org/scripts/code/1234/new-name.js",
+      metadata: {
+        ...baseMeta,
+        // 无 updateurl/downloadurl => 走 scriptcat 分支
+      } as any,
+    });
+
+    const found = await dao.searchExistingScript(target);
+    expect(found[0]?.uuid).toBe("sc-1");
+  });
+
+  it("应能在 greasyfork 场景下匹配（忽略文件名差异，基于 id 与 update/download URL）", async () => {
+    const existing = makeBaseScript({
+      uuid: "gf-1",
+      origin: "https://update.greasyfork.org/scripts/1234/old.meta.js",
+      metadata: {
+        ...baseMeta,
+        updateurl: ["https://update.greasyfork.org/scripts/1234/old.meta.js"],
+        downloadurl: ["https://update.greasyfork.org/scripts/1234/old.user.js"],
+      } as any,
+    });
+    await dao.save(existing);
+
+    const target: Script = makeBaseScript({
+      uuid: "target-2",
+      origin: "https://update.greasyfork.org/scripts/1234/new-name.meta.js",
+      metadata: {
+        ...baseMeta,
+        updateurl: ["https://update.greasyfork.org/scripts/1234/new-name.meta.js"],
+        downloadurl: ["https://update.greasyfork.org/scripts/1234/new-name.user.js"],
+      } as any,
+    });
+
+    const found = await dao.searchExistingScript(target);
+    expect(found[0]?.uuid).toBe("gf-1");
+  });
+
+  it("只有 updateurl 也可以匹配 greasyfork 脚本", async () => {
+    const existing = makeBaseScript({
+      uuid: "gf-2",
+      origin: "https://update.greasyfork.org/scripts/5678/keep.meta.js",
+      metadata: {
+        ...baseMeta,
+        updateurl: ["https://update.greasyfork.org/scripts/5678/keep.meta.js"],
+      } as any,
+    });
+    await dao.save(existing);
+
+    const target: Script = makeBaseScript({
+      uuid: "target-3",
+      origin: "https://update.greasyfork.org/scripts/5678/changed-name.meta.js",
+      metadata: {
+        ...baseMeta,
+        updateurl: ["https://update.greasyfork.org/scripts/5678/changed-name.meta.js"],
+      } as any,
+    });
+
+    const found = await dao.searchExistingScript(target);
+    expect(found[0]?.uuid).toBe("gf-2");
+  });
+
+  it("当元数据关键信息不一致（如 grant）时不应匹配", async () => {
+    const existing = makeBaseScript({
+      uuid: "mismatch-1",
+      origin: "https://scriptcat.org/scripts/code/42/old.js",
+    });
+    await dao.save(existing);
+
+    const target: Script = makeBaseScript({
+      uuid: "target-4",
+      origin: "https://scriptcat.org/scripts/code/42/new.js",
+      metadata: {
+        ...baseMeta,
+        grant: ["none"], // 与 existing 不同
+      } as any,
+    });
+
+    const found = await dao.searchExistingScript(target);
+    expect(found[0]).toBeUndefined();
+  });
+
+  it("不同域名/来源不应匹配", async () => {
+    const existing = makeBaseScript({
+      uuid: "domain-1",
+      origin: "https://scriptcat.org/scripts/code/999/old.js",
+    });
+    await dao.save(existing);
+
+    const target: Script = makeBaseScript({
+      uuid: "target-5",
+      origin: "https://update.greasyfork.org/scripts/999/new.meta.js",
+      metadata: {
+        ...baseMeta,
+        updateurl: ["https://update.greasyfork.org/scripts/999/new.meta.js"],
+      } as any,
+    });
+
+    const found = await dao.searchExistingScript(target);
+    expect(found[0]).toBeUndefined();
+  });
+});
diff --git a/src/app/repo/scripts.ts b/src/app/repo/scripts.ts
index 7b91bb9ca..11303617a 100644
--- a/src/app/repo/scripts.ts
+++ b/src/app/repo/scripts.ts
@@ -134,7 +134,7 @@ export class ScriptDAO extends Repo<Script> {
     });
   }
 
-  public findByNameAndNamespace(name: string, namespace?: string) {
+  public findByNameAndNamespace(name: string, namespace: string) {
     return this.findOne((key, value) => {
       return value.name === name && (!namespace || value.namespace === namespace);
     });
@@ -151,6 +151,99 @@ export class ScriptDAO extends Repo<Script> {
       return value.origin === origin && value.subscribeUrl === suburl;
     });
   }
+
+  public async searchExistingScript(targetScript: Script, toCheckScriptInfoEqual: boolean = true): Promise<Script[]> {
+    const removeScriptNameFromURL = (url: string) => {
+      // https://scriptcat.org/scripts/code/{id}/{scriptname}.user.js (单匹配)
+      if (url.startsWith("https://scriptcat.org/scripts/code/") && url.endsWith(".js")) {
+        const idx1 = url.indexOf("/", "https://scriptcat.org/scripts/code/".length);
+        const idx2 = url.indexOf("/", idx1 + 1);
+        if (idx1 > 0 && idx2 < 0) {
+          const idx3 = url.indexOf(".", idx1 + 1);
+          return url.substring(0, idx1 + 1) + "*" + url.substring(idx3);
+        }
+      }
+      // https://update.greasyfork.org/scripts/{id}/{scriptname}.user.js (单匹配)
+      if (url.startsWith("https://update.greasyfork.org/scripts/") && url.endsWith(".js")) {
+        const idx1 = url.indexOf("/", "https://update.greasyfork.org/scripts/".length);
+        const idx2 = url.indexOf("/", idx1 + 1);
+        if (idx1 > 0 && idx2 < 0) {
+          const idx3 = url.indexOf(".", idx1 + 1);
+          return url.substring(0, idx1 + 1) + "*" + url.substring(idx3);
+        }
+      }
+      // https://openuserjs.org/install/{username}/{scriptname}.user.js (复数匹配)
+      if (url.startsWith("https://openuserjs.org/install/") && url.endsWith(".js")) {
+        const idx1 = url.indexOf("/", "https://openuserjs.org/install/".length);
+        const idx2 = url.indexOf("/", idx1 + 1);
+        if (idx1 > 0 && idx2 < 0) {
+          const idx3 = url.indexOf(".", idx1 + 1);
+          return url.substring(0, idx1 + 1) + "*" + url.substring(idx3);
+        }
+      }
+      return url;
+    };
+    const valEqual = (val1: any, val2: any) => {
+      if (val1 && val2 && Array.isArray(val1) && Array.isArray(val2)) {
+        if (val1.length !== val2.length) return false;
+        if (val1.length < 2) {
+          return val1[0] === val2[0];
+        }
+        // 無視次序
+        const s = new Set([...val1, ...val2]);
+        if (s.size !== val1.length) return false;
+        return true;
+      }
+      return val1 === val2;
+    };
+    const isScriptInfoEqual = (script1: Script, script2: Script) => {
+      // @author, @copyright, @license 應該不會改
+      if (!valEqual(script1.metadata.author, script2.metadata.author)) return false;
+      if (!valEqual(script1.metadata.copyright, script2.metadata.copyright)) return false;
+      if (!valEqual(script1.metadata.license, script2.metadata.license)) return false;
+      // @grant, @connect 應該不會改
+      if (!valEqual(script1.metadata.grant, script2.metadata.grant)) return false;
+      if (!valEqual(script1.metadata.connect, script2.metadata.connect)) return false;
+      // @match @include 應該不會改
+      if (!valEqual(script1.metadata.match, script2.metadata.match)) return false;
+      if (!valEqual(script1.metadata.include, script2.metadata.include)) return false;
+      return true;
+    };
+
+    const { metadata, origin } = targetScript;
+
+    if (origin && !metadata?.updateurl?.[0] && !metadata?.downloadurl?.[0]) {
+      // scriptcat
+      const targetOrigin = removeScriptNameFromURL(origin);
+      return this.find((key, entry) => {
+        if (!entry.origin) return false;
+        const entryOrigin = removeScriptNameFromURL(entry.origin);
+        if (targetOrigin !== entryOrigin) return false;
+        if (toCheckScriptInfoEqual && !isScriptInfoEqual(targetScript, entry)) return false;
+        return true;
+      });
+    } else if (origin && (metadata?.updateurl?.[0] || metadata?.downloadurl?.[0])) {
+      // greasyfork
+
+      const targetOrigin = removeScriptNameFromURL(origin);
+      const targetUpdateURL = removeScriptNameFromURL(metadata?.updateurl?.[0] || "");
+      const targetDownloadURL = removeScriptNameFromURL(metadata?.downloadurl?.[0] || "");
+      return this.find((key, entry) => {
+        if (!entry.origin) return false;
+        const entryOrigin = removeScriptNameFromURL(entry.origin);
+        if (targetOrigin !== entryOrigin) return false;
+
+        const entryUpdateURL = removeScriptNameFromURL(entry.metadata?.updateurl?.[0] || "");
+        const entryDownloadURL = removeScriptNameFromURL(entry.metadata?.downloadurl?.[0] || "");
+
+        if (targetUpdateURL !== entryUpdateURL || targetDownloadURL !== entryDownloadURL) return false;
+        if (toCheckScriptInfoEqual && !isScriptInfoEqual(targetScript, entry)) return false;
+        return true;
+      });
+    } else {
+      return [];
+    }
+  }
 }
 
 // 为了防止脚本代码数据量过大,单独存储脚本代码
diff --git a/src/app/service/service_worker/client.ts b/src/app/service/service_worker/client.ts
index 2329d5d3c..5a64a0426 100644
--- a/src/app/service/service_worker/client.ts
+++ b/src/app/service/service_worker/client.ts
@@ -47,7 +47,7 @@ export class ScriptClient extends Client {
 
   // 获取安装信息
   getInstallInfo(uuid: string) {
-    return this.do<[boolean, ScriptInfo]>("getInstallInfo", uuid);
+    return this.do<[boolean, ScriptInfo, { byWebRequest?: boolean }]>("getInstallInfo", uuid);
   }
 
   install(script: Script, code: string, upsertBy: InstallSource = "user"): Promise<{ update: boolean }> {
diff --git a/src/app/service/service_worker/script.ts b/src/app/service/service_worker/script.ts
index e946e4804..109b34165 100644
--- a/src/app/service/service_worker/script.ts
+++ b/src/app/service/service_worker/script.ts
@@ -107,7 +107,7 @@ export class ScriptService {
         // 读取脚本url内容, 进行安装
         const logger = this.logger.with({ url: targetUrl });
         logger.debug("install script");
-        this.openInstallPageByUrl(targetUrl, "user")
+        this.openInstallPageByUrl(targetUrl, { source: "user", byWebRequest: true })
           .catch((e) => {
             logger.error("install script error", Logger.E(e));
             // 不再重定向当前url
@@ -205,10 +205,13 @@ export class ScriptService {
     );
   }
 
-  public async openInstallPageByUrl(url: string, source: InstallSource): Promise<{ success: boolean; msg: string }> {
+  public async openInstallPageByUrl(
+    url: string,
+    options: { source: InstallSource; byWebRequest?: boolean }
+  ): Promise<{ success: boolean; msg: string }> {
     const uuid = uuidv4();
     try {
-      await this.openUpdateOrInstallPage(uuid, url, source, false);
+      await this.openUpdateOrInstallPage(uuid, url, options, false);
       timeoutExecution(
         `${cIdKey}_cleanup_${uuid}`,
         () => {
@@ -711,7 +714,14 @@ export class ScriptService {
     return script;
   }
 
-  async openUpdateOrInstallPage(uuid: string, url: string, upsertBy: InstallSource, update: boolean, logger?: Logger) {
+  async openUpdateOrInstallPage(
+    uuid: string,
+    url: string,
+    options: { source: InstallSource; byWebRequest?: boolean },
+    update: boolean,
+    logger?: Logger
+  ) {
+    const upsertBy = options.source;
     const code = await fetchScriptBody(url);
     if (update && (await this.systemConfig.getSilenceUpdateScript())) {
       try {
@@ -735,7 +745,7 @@ export class ScriptService {
     if (!metadata) {
       throw new Error("parse script info failed");
     }
-    const si = [update, createScriptInfo(uuid, code, url, upsertBy, metadata)];
+    const si = [update, createScriptInfo(uuid, code, url, upsertBy, metadata), options];
     await cacheInstance.set(`${CACHE_KEY_SCRIPT_INFO}${uuid}`, si);
     return 1;
   }
@@ -751,7 +761,7 @@ export class ScriptService {
     });
     const url = downloadUrl || checkUpdateUrl!;
     try {
-      const ret = await this.openUpdateOrInstallPage(uuid, url, source, true, logger);
+      const ret = await this.openUpdateOrInstallPage(uuid, url, { source }, true, logger);
       if (ret === 2) return; // slience update
       // 打开安装页面
       openInCurrentTab(`/src/install.html?uuid=${uuid}`);
@@ -1141,7 +1151,7 @@ export class ScriptService {
   }
 
   importByUrl(url: string) {
-    return this.openInstallPageByUrl(url, "user");
+    return this.openInstallPageByUrl(url, { source: "user" });
   }
 
   setCheckUpdateUrl({
diff --git a/src/app/service/service_worker/subscribe.ts b/src/app/service/service_worker/subscribe.ts
index 4eb397b02..0a9b27e32 100644
--- a/src/app/service/service_worker/subscribe.ts
+++ b/src/app/service/service_worker/subscribe.ts
@@ -231,7 +231,7 @@ export class SubscribeService {
         if (true === (await this.trySilenceUpdate(code, url))) {
           // slience update
         } else {
-          const si = [false, createScriptInfo(uuid, code, url, source, metadata)];
+          const si = [false, createScriptInfo(uuid, code, url, source, metadata), {}];
           await cacheInstance.set(`${CACHE_KEY_SCRIPT_INFO}${uuid}`, si);
           chrome.tabs.create({
             url: `/src/install.html?uuid=${uuid}`,
diff --git a/src/pages/install/App.tsx b/src/pages/install/App.tsx
index 95f62360a..6207af32a 100644
--- a/src/pages/install/App.tsx
+++ b/src/pages/install/App.tsx
@@ -88,10 +88,12 @@ function App() {
       const uuid = locationUrl.searchParams.get("uuid");
       let info: ScriptInfo | undefined;
       let isKnownUpdate: boolean = false;
+      let paramOptions = {};
       if (uuid) {
         const cachedInfo = await scriptClient.getInstallInfo(uuid);
         if (cachedInfo?.[0]) isKnownUpdate = true;
         info = cachedInfo?.[1] || undefined;
+        paramOptions = cachedInfo?.[2] || {};
         if (!info) {
           throw new Error("fetch script info failed");
         }
@@ -145,7 +147,7 @@ function App() {
         diffCode = prepare.oldSubscribe?.code;
       } else {
         const knownUUID = isKnownUpdate ? info.uuid : undefined;
-        prepare = await prepareScriptByCode(code, url, knownUUID);
+        prepare = await prepareScriptByCode(code, url, knownUUID, false, undefined, paramOptions);
         action = prepare.script;
         if (prepare.oldScript) {
           oldVersion = prepare.oldScript!.metadata!.version![0] || "";
diff --git a/src/pkg/utils/script.ts b/src/pkg/utils/script.ts
index f99c49c26..516cd353b 100644
--- a/src/pkg/utils/script.ts
+++ b/src/pkg/utils/script.ts
@@ -84,6 +84,7 @@ export async function prepareScriptByCode(
   dao?: ScriptDAO,
   options?: {
     byEditor?: boolean; // 是否通过编辑器导入
+    byWebRequest?: boolean; // 是否通过網頁連結安裝或更新
   }
 ): Promise<{ script: Script; oldScript?: Script; oldScriptCode?: string }> {
   dao = dao ?? new ScriptDAO();
@@ -131,7 +132,7 @@ export async function prepareScriptByCode(
     uuid: newUUID,
     name: metadata.name[0],
     author: metadata.author && metadata.author[0],
-    namespace: metadata.namespace && metadata.namespace[0],
+    namespace: metadata.namespace[0], // 上面的代码已检查 meta.namespace, 不会为undefined
     originDomain: domain,
     origin,
     checkUpdate: true,
@@ -156,6 +157,24 @@ export async function prepareScriptByCode(
   if (!old && (!uuid || override)) {
     old = await dao.findByNameAndNamespace(script.name, script.namespace);
   }
+  if (!old && options?.byWebRequest) {
+    const test = await dao.searchExistingScript(script);
+    if (test.length === 1) {
+      const testCheckUrl = test[0]?.checkUpdateUrl;
+      if (testCheckUrl) {
+        // 尝试下载该脚本的url, 检查是否指向要求脚本
+        try {
+          const code = await fetchScriptBody(testCheckUrl);
+          const metadata = code ? parseMetadata(code) : null;
+          if (metadata && metadata.name![0] === script.name && (metadata.namespace?.[0] || "") === script.namespace) {
+            old = test[0];
+          }
+        } catch {
+          /* empty */
+        }
+      }
+    }
+  }
   if (old) {
     if (
       (old.type === SCRIPT_TYPE_NORMAL && script.type !== SCRIPT_TYPE_NORMAL) ||