Abstract: The low temperature waste heat utilization project of Zhao Gu Coal Mine was tested in this paper and found that the system runs stably. However, the utilization rate of parallel heat of multiple low temperature heat sources is low, the model of the system was established by TRNSYS software and the correctness of the model is verified by the existing system, the model is used to analyze the heat utilization rate of multiple low temperature heat sources in series, the results show that Multiple low temperature heat sources in series are more efficient than in parallel, and it indicates the direction for the optimization of the system, provides a reference for the design of the same type project.