In teleoperation of a crawler robot in a disasterstricken enclosed space, distress of the crawler robot due to communication breakdown is a problem. We present a robot teleoperation system using LoRaWAN as a subcommunication infrastructure to solve this problem. In this system, the crawler robot is operated by teleoperation using a subcommunication infrastructure in a place where a wireless local area network (LAN) communication is possible. In this study, we assume an environment in which the crawler robot must ascend and descend stairs to evacuate to a place where wireless LAN communication is possible. In addition, the disaster-stricken environment is considered as an environment where obstacles are expected to suddenly occur, and the crawler robot has difficulty avoiding obstacles on the stairs. In this paper, we propose a teleoperation communication protocol that considers the risk of sudden appearance of obstacles and confirm its effectiveness using evaluation experiments in a real environment.