diff --git a/ractor.rb b/ractor.rb
index b5b2677a2b..2196a93352 100644
--- a/ractor.rb
+++ b/ractor.rb
@@ -139,7 +139,7 @@ class Ractor
     Primitive.ractor_receive_if b
   end
 
-  def receive_if &b
+  private def receive_if &b
     Primitive.ractor_receive_if b
   end