diff --git a/build.rs b/build.rs
index 8db0adf77..c21b7b985 100644
--- a/build.rs
+++ b/build.rs
@@ -78,7 +78,7 @@ fn install_oboe() {
 
 #[cfg(feature = "flutter")]
 fn gen_flutter_rust_bridge() {
-    if std::env::var("RUN_FFIGEN").is_ok() {
+    if !std::env::var("RUN_FFIGEN").is_ok() {
         return;
     }
     use lib_flutter_rust_bridge_codegen::{