Abstract:A modified BP algorithm of neural network,random adjustment of parameters (RMBP) algorithm,is proposed to overcome the defect of easy going into local minimum of BP neural network.By adding randomization to the progress of parameters adjustment,RMBP helps BP neural network jump out of local minimum point easily,and get to global minimum point along gradient descent direction.Result of study experiment of XOR problem shows that RMBP has advantages of high study speed,high study precision and low resource occupation in comparison with other modified or unmodified BP algorithm.Finally,in combination with study of real-time flight simulation system of civil aviation airplane,a study is made of a group of aircraft aerodynamic force character parameters to verify the effectiveness of RMBP algorithm.