diff --git a/packages/docusaurus-plugin-content-docs/src/sidebars/index.ts b/packages/docusaurus-plugin-content-docs/src/sidebars/index.ts
index 6af73d22ad0d..1828e9560124 100644
--- a/packages/docusaurus-plugin-content-docs/src/sidebars/index.ts
+++ b/packages/docusaurus-plugin-content-docs/src/sidebars/index.ts
@@ -43,6 +43,7 @@ export function resolveSidebarPathOption(
 async function readCategoriesMetadata(contentPath: string) {
   const categoryFiles = await Globby('**/_category_.{json,yml,yaml}', {
     cwd: contentPath,
+    ignore: ['**/node_modules/**'],
   });
   const categoryToFile = _.groupBy(categoryFiles, path.dirname);
   return combinePromises(
diff --git a/packages/docusaurus-utils/src/__tests__/globUtils.test.ts b/packages/docusaurus-utils/src/__tests__/globUtils.test.ts
index 709671e916b1..644e3d54b7af 100644
--- a/packages/docusaurus-utils/src/__tests__/globUtils.test.ts
+++ b/packages/docusaurus-utils/src/__tests__/globUtils.test.ts
@@ -27,6 +27,18 @@ describe('isTranslatableSourceFile', () => {
 });
 
 describe('createMatcher', () => {
+  it('match default exclude node_modules correctly', () => {
+    const matcher = createMatcher(GlobExcludeDefault);
+    expect(matcher('node_modules/pkg/doc.md')).toBe(true);
+    expect(matcher('node_modules/pkg/index.js')).toBe(true);
+    expect(matcher('category/node_modules/pkg/doc.md')).toBe(true);
+    expect(matcher('category/node_modules/@scope/pkg/doc.md')).toBe(true);
+    // When contentPath is inside node_modules, relative paths of content
+    // files do NOT contain node_modules, so they should NOT be excluded.
+    expect(matcher('intro.md')).toBe(false);
+    expect(matcher('guide/setup.mdx')).toBe(false);
+  });
+
   it('match default exclude MD/MDX partials correctly', () => {
     const matcher = createMatcher(GlobExcludeDefault);
     expect(matcher('doc.md')).toBe(false);
@@ -115,6 +127,36 @@ describe('createAbsoluteFilePathMatcher', () => {
     expect(matcher('/root/_docs/_category/myDoc.mdx')).toBe(true);
   });
 
+  it('match default exclude node_modules correctly', () => {
+    expect(matcher('/_root/docs/node_modules/pkg/doc.md')).toBe(true);
+    expect(matcher('/_root/docs/node_modules/@scope/pkg/doc.md')).toBe(true);
+    expect(
+      matcher('/_root/docs/category/node_modules/pkg/index.js'),
+    ).toBe(true);
+  });
+
+  // Ensures that when contentPath is inside node_modules (e.g.,
+  // node_modules/@myCompany/docs), content files at that root are NOT
+  // excluded, because their relative paths don't contain node_modules.
+  it('does not exclude content when root folder is inside node_modules', () => {
+    const nmMatcher = createAbsoluteFilePathMatcher(GlobExcludeDefault, [
+      '/project/node_modules/@myCompany/docs',
+    ]);
+    // Content at the root should NOT be excluded
+    expect(
+      nmMatcher('/project/node_modules/@myCompany/docs/intro.md'),
+    ).toBe(false);
+    expect(
+      nmMatcher('/project/node_modules/@myCompany/docs/guide/setup.mdx'),
+    ).toBe(false);
+    // But nested node_modules inside that root SHOULD be excluded
+    expect(
+      nmMatcher(
+        '/project/node_modules/@myCompany/docs/node_modules/dep/file.md',
+      ),
+    ).toBe(true);
+  });
+
   it('match default exclude tests correctly', () => {
     expect(matcher('/__test__/website/src/xyz.js')).toBe(false);
     expect(matcher('/__test__/website/src/__test__/xyz.js')).toBe(true);
diff --git a/packages/docusaurus-utils/src/globUtils.ts b/packages/docusaurus-utils/src/globUtils.ts
index c26e84ab65d7..99f109b4d2ed 100644
--- a/packages/docusaurus-utils/src/globUtils.ts
+++ b/packages/docusaurus-utils/src/globUtils.ts
@@ -26,6 +26,7 @@ export const Globby = Tinyglobby.glob;
  * - Ignore tests
  */
 export const GlobExcludeDefault = [
+  '**/node_modules/**',
   '**/_*.{js,jsx,ts,tsx,md,mdx}',
   '**/_*/**',
   '**/*.test.{js,jsx,ts,tsx}',