Based on the projection pursuit regression (PPR) principle, the PPR model has been set up with 15 independent variables such as b value, C_b value, A_b value etc., which are selected from seismometry parameters and one dependent variable representing maximum magnitude of earthquake that would occur in coming several months. By using the model,maximum magnitude of coming earthquake and probability of earthquake to occur in the future can be predicted.The PPR model of four mainly seismic regions in Xinjiang and their ridge functions are showed. The prediction effects of reservation test and practical test are satisfactory.