diff --git a/system/taskset/taskset.c b/system/taskset/taskset.c
index 650150d98..3cffd2e28 100644
--- a/system/taskset/taskset.c
+++ b/system/taskset/taskset.c
@@ -138,7 +138,8 @@ int main(int argc, FAR char *argv[])
           goto errout;
         }
 
-      printf("pid %d's current affinity mask: %x\n", pid, cpuset);
+      printf("pid %d's current affinity mask: 0x%" PRIx32 "\n", pid,
+             (uint32_t)cpuset);
     }
   else
     {