diff --git a/src/core/transport/transport.h b/src/core/transport/transport.h
index 60193b1..ce8c17c 100644
--- a/src/core/transport/transport.h
+++ b/src/core/transport/transport.h
@@ -31,8 +31,8 @@
  *
  */
 
-#ifndef __GRPC_INTERNAL_TRANSPORT_TRANSPORT_H__
-#define __GRPC_INTERNAL_TRANSPORT_TRANSPORT_H__
+#ifndef GRPC_INTERNAL_CORE_TRANSPORT_TRANSPORT_H
+#define GRPC_INTERNAL_CORE_TRANSPORT_TRANSPORT_H
 
 #include <stddef.h>
 
@@ -254,4 +254,4 @@
    used as a destruction call by setup). */
 void grpc_transport_setup_cancel(grpc_transport_setup *setup);
 
-#endif /* __GRPC_INTERNAL_TRANSPORT_TRANSPORT_H__ */
+#endif  /* GRPC_INTERNAL_CORE_TRANSPORT_TRANSPORT_H */