In order to build a highly reliable equivalent transient model of PV power generator under grid fault, as well as establish a solid basis for the fault feature and relay protection study of the power grid with PV power generators, a controller parameter identification method of the grid connected PV inverter for fault transient modeling is proposed. The proposed parameter identification method is based on the differential evolution algorithm. With the proposed method, both the proportional gains and integral gains of the PI regulators and the limiter values can be correctly identified, which can make up the shortage of traditional controller parameter identification methods and ensure the accuracy of the fault transient modeling of the PV power generator. Moreover, the stepwise identification procedure of controller parameters is put forward, and the initial values of the initial population are set according to the theoretical calculation, to improve the convergence rate of the identified parameters and efficiency of the identification method.