Radar evaluation refers to the means by which differential GNSS is used to obtain the High-precision path of the flying carrier, to evaluate the radar acquisition accuracy and check the overall performance and technological specifications of the radar. The system comprises a High-precision GNSS receiver with memory, high-dynamic receiving antenna and High-precision post-processing dynamic calculating software. During calibration flight, the GNSS base station and rover station, installed on the ground-based radar and aircraft, acquire data of the flight path with their built-in memory cards in the calibration flight; after completion of flight, GrafNav post-processing software calculates the High-precision flight path of the carrier with the flight data, to provide precise reference for evaluating the radar.