diff --git a/types/react-css-collapse/tsconfig.json b/types/react-css-collapse/tsconfig.json
index 4af49b9769..efb2921718 100644
--- a/types/react-css-collapse/tsconfig.json
+++ b/types/react-css-collapse/tsconfig.json
@@ -7,7 +7,7 @@
         ],
         "noImplicitAny": true,
         "noImplicitThis": true,
-        "strictNullChecks": false,
+        "strictNullChecks": true,
         "strictFunctionTypes": true,
         "baseUrl": "../",
         "typeRoots": [