diff --git a/esp8266/main.c b/esp8266/main.c
index 0224bed488..21bb6e0e0f 100644
--- a/esp8266/main.c
+++ b/esp8266/main.c
@@ -57,6 +57,7 @@ STATIC void mp_reset(void) {
     #endif
     MP_STATE_PORT(mp_kbd_exception) = mp_obj_new_exception(&mp_type_KeyboardInterrupt);
     MP_STATE_PORT(term_obj) = MP_OBJ_NULL;
+    MP_STATE_PORT(dupterm_arr_obj) = MP_OBJ_NULL;
     pin_init0();
     readline_init0();
 #if MICROPY_MODULE_FROZEN