In the Monitor System granary temperature and humidity, and air is an important granary environment monitoring data. The continuous development of Internet technology, wireless sensor technology and 4G technology provides stable technical conditions for the monitoring of temperature and humidity in granary. The final part of wireless sensor network technology is wireless sensor network technology. Wireless sensor network technology mainly consists of three parts: node, sink node and management node. This paper will deeply analyze the implementation strategy of wireless sensor network in temperature and humidity monitoring system of granary.