Abstract: Based on solar thermal utilization system,energy potential analysis model is established to evaluate some key processes in solar thermal energy utilization technology,which include the solar concentrating process,conversion of thermal energy to power and solar-thermochemical utilization,and to compare the two utilization methods. The results show that the mismatching of solar energy and working fluid is the key factor limiting the efficiency of solar thermal utilization system. The results are expected to guide the solar thermal utilization technology.