diff --git a/packages/gatsby/src/redux/types.ts b/packages/gatsby/src/redux/types.ts
index d0f56999baa77..b8de89660905a 100644
--- a/packages/gatsby/src/redux/types.ts
+++ b/packages/gatsby/src/redux/types.ts
@@ -92,6 +92,7 @@ export interface IGatsbyConfig {
   developMiddleware?: any
   proxy?: any
   pathPrefix?: string
+  assetPrefix?: string
   mapping?: Record<string, string>
 }