diff --git a/libcpu/sim/posix/cpu_port.c b/libcpu/sim/posix/cpu_port.c
index 636f82cde1..9561fe9f6c 100644
--- a/libcpu/sim/posix/cpu_port.c
+++ b/libcpu/sim/posix/cpu_port.c
@@ -503,8 +503,6 @@ static void start_sys_timer(void)
     struct itimerval itimer, oitimer;
     int us;
 
-    RT_ASSERT(RT_TICK_PER_SECOND <= 1000000 || RT_TICK_PER_SECOND >= 1);
-
     us = 1000000 / RT_TICK_PER_SECOND - 1;
 
     TRACE("start system tick!\n");