diff --git a/bsp/raspberry-pi/raspi4-32/applications/main.c b/bsp/raspberry-pi/raspi4-32/applications/main.c
index f03904bb10910b24668b00c32b972e220c6bb8a1..6a1321235e7e6231f0c3dc443d127c15e13094d6 100644
--- a/bsp/raspberry-pi/raspi4-32/applications/main.c
+++ b/bsp/raspberry-pi/raspi4-32/applications/main.c
@@ -7,7 +7,7 @@
  * Date           Author       Notes
  * 2017-5-30     bernard       the first version
  */
-
+#include <rtthread.h>
 #include <stdio.h>
 
 int main(int argc, char** argv)