diff --git a/packages/vitest/src/types/happy-dom-options.ts b/packages/vitest/src/types/happy-dom-options.ts
index 6c57cb9dae56..67a7b69584be 100644
--- a/packages/vitest/src/types/happy-dom-options.ts
+++ b/packages/vitest/src/types/happy-dom-options.ts
@@ -12,6 +12,9 @@ export interface HappyDOMOptions {
     disableIframePageLoading?: boolean
     disableComputedStyleRendering?: boolean
     enableFileSystemHttpRequests?: boolean
+    navigator?: {
+      userAgent?: string
+    }
     device?: {
       prefersColorScheme?: string
       mediaType?: string