diff --git a/types/swagger-ui-express/tsconfig.json b/types/swagger-ui-express/tsconfig.json
index c64deb2feb..dfb989be63 100644
--- a/types/swagger-ui-express/tsconfig.json
+++ b/types/swagger-ui-express/tsconfig.json
@@ -7,7 +7,7 @@
         "noImplicitAny": true,
         "noImplicitThis": true,
         "strictNullChecks": true,
-        "strictFunctionTypes": false,
+        "strictFunctionTypes": true,
         "baseUrl": "../",
         "typeRoots": [
             "../"