diff --git a/code/addons/test/package.json b/code/addons/test/package.json
index 8985ab45459c..35a4077926e1 100644
--- a/code/addons/test/package.json
+++ b/code/addons/test/package.json
@@ -112,6 +112,7 @@
     "slash": "^5.0.0",
     "strip-ansi": "^7.1.0",
     "tinyglobby": "^0.2.10",
+    "tree-kill": "^1.2.2",
     "ts-dedent": "^2.2.0",
     "typescript": "^5.3.2",
     "vitest": "^2.1.3"
diff --git a/code/addons/test/src/vitest-plugin/global-setup.ts b/code/addons/test/src/vitest-plugin/global-setup.ts
index bff48208229a..ca287c105e2b 100644
--- a/code/addons/test/src/vitest-plugin/global-setup.ts
+++ b/code/addons/test/src/vitest-plugin/global-setup.ts
@@ -5,6 +5,8 @@ import type { GlobalSetupContext } from 'vitest/node';
 
 import { logger } from 'storybook/internal/node-logger';
 
+import treeKill from 'tree-kill';
+
 let storybookProcess: ChildProcess | null = null;
 
 const getIsVitestStandaloneRun = () => {
@@ -59,14 +61,6 @@ const startStorybookIfNotRunning = async () => {
   }
 };
 
-const killProcess = (process: ChildProcess) => {
-  return new Promise((resolve, reject) => {
-    process.on('close', resolve);
-    process.on('error', reject);
-    process.kill();
-  });
-};
-
 export const setup = async ({ config }: GlobalSetupContext) => {
   if (config.watch && isVitestStandaloneRun) {
     await startStorybookIfNotRunning();
@@ -74,8 +68,19 @@ export const setup = async ({ config }: GlobalSetupContext) => {
 };
 
 export const teardown = async () => {
-  if (storybookProcess) {
-    logger.verbose('Stopping Storybook process');
-    await killProcess(storybookProcess);
+  if (!storybookProcess) {
+    return;
   }
+  logger.verbose('Stopping Storybook process');
+  await new Promise<void>((resolve, reject) => {
+    // Storybook starts multiple child processes, so we need to kill the whole tree
+    treeKill(storybookProcess.pid, 'SIGTERM', (error) => {
+      if (error) {
+        logger.error('Failed to stop Storybook process:');
+        reject(error);
+        return;
+      }
+      resolve();
+    });
+  });
 };
diff --git a/code/yarn.lock b/code/yarn.lock
index e6f690cb347c..32615bb80a66 100644
--- a/code/yarn.lock
+++ b/code/yarn.lock
@@ -6426,6 +6426,7 @@ __metadata:
     slash: "npm:^5.0.0"
     strip-ansi: "npm:^7.1.0"
     tinyglobby: "npm:^0.2.10"
+    tree-kill: "npm:^1.2.2"
     ts-dedent: "npm:^2.2.0"
     typescript: "npm:^5.3.2"
     vitest: "npm:^2.1.3"
@@ -27745,7 +27746,7 @@ __metadata:
   languageName: node
   linkType: hard
 
-"tree-kill@npm:1.2.2":
+"tree-kill@npm:1.2.2, tree-kill@npm:^1.2.2":
   version: 1.2.2
   resolution: "tree-kill@npm:1.2.2"
   bin: