The design technology of multi-point temperature cycle test circuit in granary is the key technology for scientific regulation of grain safety. In view of the particularity of grain storage, the system function should focus on the detection and analysis of the internal temperature of grain storage. Based on AT89S52 single chip microcomputer, this paper designs and introduces the temperature cycle test circuit design of American Dallas semiconductor digital temperature sensor DS 18B20 granary multi-ple sensor by using C language programming, and analyzes the results of actual operation data. In this paper, taking the 8-way granary temperature acquisition and detection system as an example, the eight synchronous fast ports DS 18B20 of P 1 are read by AT89S52 single chip microcomputer, which realizes the rapid and accurate identification and addressing of multiple sensors in the multi-way temperature measurement system, and adopts two control loop detection modes to automatically select the single detection mode respectively, and gives the concrete realization, simulation results and experimental data. Managers can check the real-time temperature data without site, comprehensively analyze and predict the grain disaster, and realize the automation and intelligence of granary temperature management.