Abstract: In order to improve the water production performance and reduce the internal fouling,a flash evaporation desalination system with a non-tracking parabolic concentrator to heat the heat transfer oil to over 100 ℃ as an energy supply source and spray assisted flash was developed. The influences of water inlet temperature and flow rate on the fresh water production performance under different solar irradiance were experimentally explored in actual weather. The water inlet temperature can be enhanced above the boiling point（up to123 ℃）by employing the sealed tank. In experiments,when the solar irradiance fluctuates greatly,the water inlet temperature remains stable and the system can operate stably. The water inlet temperature has a significant influence on the water production. When the average water inlet temperature increases from 100 ℃ to 120 ℃,the water production rate increases by 47.61%. When the water inlet flow rate is 50 kg/h and the pressure is 0.045 MPa,the system has the largest water production rate. The daily cumulative fresh water production reach 11.14 kg/（d·m~2）,the hourly efficiency is 81.45%,and the single-stage productivity is 9.15%.