In order to solve the difficulty of obtaining the basic probability assignment(BPA)and the low applicability of genera-tion model in D-S evidence theory application,a basic probabilistic assignment generation method combining nearest neighbor density and information correction was proposed.A single focal element BPA function was generated based on the distance be-tween the peak density point and the sample data derived from the K-nearest neighbor(KNN)algorithm;the values were as-signed to the whole subset of events by belief x2 divergence and BPA information was modified based on confidence.The im-proved belief entropy formula was utilized to compute the uncertainty weight of each piece of evidence for evidence redistribu-tion.The generated BPA is utilized to solve the practical application problems of few samples and imbalanced class samples,and the diagnostic accuracies of the proposed method are all over 85%,which are better than other methods,as verified by multiple datasets.