Abstract: Based on PVsyst,the annual power generation of bifacial photovoltaic modules under different installation conditions is simulated. The simulation data is processed by regression analysis. Aiming at the defects of linear regression model,the mechanism of influence of installation factors on bifacial gain is analyzed to determine the basic functions and establish a non-linear model. This model is of good accuracy with mean absolute percentage error of 11.31%. In addition,path analysis is used to compare the influence of the installation factors on bifacial gain. The results show that albedo has the greatest influence,followed by diffuse coefficient,height and tilted angle.