diff --git a/devicemodel/hw/uart_core.c b/devicemodel/hw/uart_core.c
index 33da09c40..1b67d2979 100644
--- a/devicemodel/hw/uart_core.c
+++ b/devicemodel/hw/uart_core.c
@@ -715,6 +715,16 @@ uart_release_backend(struct uart_vdev *uart, const char *opts)
 	if (opts == NULL)
 		return;
 
+	/*
+	 * By current design, for the invalid PTY parameters, the virtual uarts
+	 * are still expose to UOS but all data be dropped by backend service.
+	 * The uart backend is not setup for this case, so don't try to release
+	 * the uart backend in here.
+	 * TODO: need re-visit the whole policy for such scenario in future.
+	 */
+	if (!uart->tty.opened)
+		return;
+
 	uart_closetty(uart);
 	if (strcmp("stdio", opts) == 0) {
 		stdio_in_use = false;