diff --git a/packages/mocker/src/node/resolver.ts b/packages/mocker/src/node/resolver.ts
index 888f404b01ac..834472b22ea0 100644
--- a/packages/mocker/src/node/resolver.ts
+++ b/packages/mocker/src/node/resolver.ts
@@ -103,7 +103,10 @@ export class ServerMockResolver {
   }
 
   private async resolveMockId(rawId: string, importer: string) {
-    if (!importer.startsWith(this.server.config.root)) {
+    if (
+      !this.server.moduleGraph.getModuleById(importer)
+      && !importer.startsWith(this.server.config.root)
+    ) {
       importer = join(this.server.config.root, importer)
     }
     const resolved = await this.server.pluginContainer.resolveId(
diff --git a/test/browser/fixtures/mocking-out-of-root/project1/basic.test.js b/test/browser/fixtures/mocking-out-of-root/project1/basic.test.js
index 3aed726e695d..d12dff4824e7 100644
--- a/test/browser/fixtures/mocking-out-of-root/project1/basic.test.js
+++ b/test/browser/fixtures/mocking-out-of-root/project1/basic.test.js
@@ -1,5 +1,7 @@
 import { test, expect, vi } from 'vitest';
 import project2 from "../project2/index.js"
+import "./imported-test.js"
+import "../project3/imported-test.js"
 
 vi.mock("../project2/index.js", () => ({
   default: 'project2-mocked'
diff --git a/test/browser/fixtures/mocking-out-of-root/project1/imported-test.js b/test/browser/fixtures/mocking-out-of-root/project1/imported-test.js
new file mode 100644
index 000000000000..7744dbdd443b
--- /dev/null
+++ b/test/browser/fixtures/mocking-out-of-root/project1/imported-test.js
@@ -0,0 +1,8 @@
+import { vi, test, expect } from "vitest"
+import lib from "./lib.js";
+
+vi.mock("./lib.js", () => ({ default: "mocked" }))
+
+test("project1 imported", () => {
+  expect(lib).toBe("mocked");
+})
diff --git a/test/browser/fixtures/mocking-out-of-root/project1/lib.js b/test/browser/fixtures/mocking-out-of-root/project1/lib.js
new file mode 100644
index 000000000000..6d9bb612b1bb
--- /dev/null
+++ b/test/browser/fixtures/mocking-out-of-root/project1/lib.js
@@ -0,0 +1 @@
+export default "lib"
diff --git a/test/browser/fixtures/mocking-out-of-root/project3/imported-test.js b/test/browser/fixtures/mocking-out-of-root/project3/imported-test.js
new file mode 100644
index 000000000000..23c25e106347
--- /dev/null
+++ b/test/browser/fixtures/mocking-out-of-root/project3/imported-test.js
@@ -0,0 +1,8 @@
+import { vi, test, expect } from "vitest"
+import lib from "./lib.js";
+
+vi.mock("./lib.js", () => ({ default: "mocked" }))
+
+test("project3 imported", () => {
+  expect(lib).toBe("mocked");
+})
diff --git a/test/browser/fixtures/mocking-out-of-root/project3/lib.js b/test/browser/fixtures/mocking-out-of-root/project3/lib.js
new file mode 100644
index 000000000000..6d9bb612b1bb
--- /dev/null
+++ b/test/browser/fixtures/mocking-out-of-root/project3/lib.js
@@ -0,0 +1 @@
+export default "lib"