A total of 3211 fault cases of Doppler weather radar of various models in recent 5 years are classified and analyzed for 9 radar subsystems. The results indicate that it is necessary for these that work under high voltage for a long time and are vulnerable, to burnout to strengthen the backup of spare parts and improve the reliability of these spare parts and to improve the reliability and resistance to pressure. Moreover, the machine room environment should have constant temperature and humidity, as well as dust proof to keep radar operating normally. It is also important to clean carbon dusts in the motor and maintain and clean the collector ring to prevent carbon brush abrasion and damage. Meanwhile, regular maintenance of the mechanical devices under high/low temperature environment for a long time is also needed in order to improve the reliability of moving parts. The power supply and data communication with external users are also important.