diff --git a/test/scripts/package-root-args.test.ts b/test/scripts/package-root-args.test.ts
index ea02420b9635..6b48f38e3dd3 100644
--- a/test/scripts/package-root-args.test.ts
+++ b/test/scripts/package-root-args.test.ts
@@ -1,27 +1,19 @@
 import path from "node:path";
-import { afterEach, describe, expect, it } from "vitest";
+import { describe, expect, it } from "vitest";
 import { parsePackageRootArg } from "../../scripts/lib/package-root-args.mjs";
+import { withEnv } from "../../src/test-utils/env.js";
 
 const ENV_NAME = "OPENCLAW_PACKAGE_ROOT_ARGS_TEST";
-const originalEnvValue = process.env[ENV_NAME];
-
-afterEach(() => {
-  if (originalEnvValue === undefined) {
-    delete process.env[ENV_NAME];
-    return;
-  }
-  process.env[ENV_NAME] = originalEnvValue;
-});
 
 describe("package-root-args", () => {
   it("uses the package root flag before the environment fallback", () => {
-    process.env[ENV_NAME] = "/env/root";
-
-    expect(parsePackageRootArg(["--package-root", "package"], ENV_NAME)).toEqual({
-      packageRoot: path.resolve("package"),
-    });
-    expect(parsePackageRootArg(["--package-root=dist/package"], ENV_NAME)).toEqual({
-      packageRoot: path.resolve("dist/package"),
+    withEnv({ [ENV_NAME]: "/env/root" }, () => {
+      expect(parsePackageRootArg(["--package-root", "package"], ENV_NAME)).toEqual({
+        packageRoot: path.resolve("package"),
+      });
+      expect(parsePackageRootArg(["--package-root=dist/package"], ENV_NAME)).toEqual({
+        packageRoot: path.resolve("dist/package"),
+      });
     });
   });