To evaluate the landing precision of precise airdrop system scientifically and effectively, put forward the precision evaluation method of precise airdrop system. Based on circular error probability (CEP) method, get landing error data, eliminate the abnormal data through error analysis on airdrop test, acquire inspections of normality and correlation on test sample, and calculate CEP by using relevant mathematical statistical methods. The analysis of the experimental data with this method has indicated its incomparable capacity of providing data support for precise airdrop system evaluation.