diff --git a/src/rtos/rtos.c b/src/rtos/rtos.c
index 136d93bf62..0df1182c0a 100644
--- a/src/rtos/rtos.c
+++ b/src/rtos/rtos.c
@@ -78,6 +78,7 @@ static void os_free(struct target *target)
 		return;
 
 	free(target->rtos->symbols);
+	rtos_free_threadlist(target->rtos);
 	free(target->rtos);
 	target->rtos = NULL;
 }