diff --git a/src/use-swr.ts b/src/use-swr.ts
index fb09e9325..a045e665f 100644
--- a/src/use-swr.ts
+++ b/src/use-swr.ts
@@ -299,10 +299,8 @@ function useSWR<Data = any, Error = any>(
           // we don't have an error
           newState.error = undefined
         }
-        if (config.compare(stateRef.current.data, newData)) {
+        if (!config.compare(stateRef.current.data, newData)) {
           // deep compare to avoid extra re-render
-          // do nothing
-        } else {
           // data changed
           newState.data = newData
         }