diff --git a/kernel/src/driver/tty/kthread.rs b/kernel/src/driver/tty/kthread.rs
index 9016b0d1..28b2fa2b 100644
--- a/kernel/src/driver/tty/kthread.rs
+++ b/kernel/src/driver/tty/kthread.rs
@@ -62,6 +62,10 @@ fn tty_refresh_thread() -> i32 {
 
 /// 发送数据到tty刷新线程
 pub fn send_to_tty_refresh_thread(data: &[u8]) {
+    if unsafe { TTY_REFRESH_THREAD.is_none() } {
+        return;
+    }
+
     for item in data {
         KEYBUF.push(*item).ok();
     }