In recent years, the advertising industry and the media industry have developed rapidly, and the use of outdoor LED screens has also increased dramatically. But there is no open system for unified management of outdoor LED display. As a result, the way through maintenance personnel check the equipment waste a lot of laboring. Therefore, this paper proposes a monitoring system for outdoor LED display based on NB-IoT technology to overcome laboring wasting, the basic information management of outdoor LED display, and the unified remote operation of task management, which provides convenience for outdoor equipment maintenance and other services. In our scheme, the narrow band Internet module is combined with the outdoor LED display as the terminal, and then the detection results are transferred to the open platform through the NB-IoT module, and the monitoring information is viewed at the APP.