diff --git a/packages/storybook/src/generators/init/init.spec.ts b/packages/storybook/src/generators/init/init.spec.ts
index 36338752e5e42..7c76df1b55fb1 100644
--- a/packages/storybook/src/generators/init/init.spec.ts
+++ b/packages/storybook/src/generators/init/init.spec.ts
@@ -3,6 +3,8 @@ import {
   type NxJsonConfiguration,
   type Tree,
   ProjectGraph,
+  updateNxJson,
+  readNxJson,
 } from '@nx/devkit';
 import { createTreeWithEmptyWorkspace } from '@nx/devkit/testing';
 import { initGenerator } from './init';
@@ -56,4 +58,30 @@ describe('@nx/storybook:init', () => {
     });
     expect(tree.read('.gitignore', 'utf-8')).toMatchSnapshot();
   });
+
+  it('should not duplicate cacheable operations in nx.json', async () => {
+    // ARRANGE
+    const nxJson = readNxJson(tree);
+    nxJson.tasksRunnerOptions ??= {};
+    nxJson.tasksRunnerOptions.default ??= {};
+    nxJson.tasksRunnerOptions.default.options ??= {};
+    nxJson.tasksRunnerOptions.default.options.cacheableOperations = [
+      'build-storybook',
+    ];
+    updateNxJson(tree, nxJson);
+
+    // ACT
+    await initGenerator(tree, {
+      addPlugin: false,
+    });
+
+    // ASSERT
+    const updatedNxJson = readNxJson(tree);
+    expect(updatedNxJson.tasksRunnerOptions.default.options.cacheableOperations)
+      .toMatchInlineSnapshot(`
+      [
+        "build-storybook",
+      ]
+    `);
+  });
 });
diff --git a/packages/storybook/src/generators/init/init.ts b/packages/storybook/src/generators/init/init.ts
index de90427a8269d..452031928ea72 100644
--- a/packages/storybook/src/generators/init/init.ts
+++ b/packages/storybook/src/generators/init/init.ts
@@ -57,7 +57,7 @@ function addCacheableOperation(tree: Tree) {
   const cacheableOperations: string[] | null =
     nxJson.tasksRunnerOptions?.default?.options?.cacheableOperations;
 
-  if (cacheableOperations && cacheableOperations.includes('build-storybook')) {
+  if (cacheableOperations && !cacheableOperations.includes('build-storybook')) {
     nxJson.tasksRunnerOptions.default.options.cacheableOperations.push(
       'build-storybook'
     );