In the radar precision flight test, the size, shape and radar cross section (RCS) etc. of the test aircraft will have an impact on the test data. The impact of different test aircraft on radar accuracy flight test data is analyzed from three aspects: azimuth error, distance error and height error. By analyzing and calculating the error of the two kinds of aircrafts on the test data, it is proposed to use different aircraft for radar test. The principle method of precision test can be used to guide the selection of aircraft for radar accuracy test.