Current disturbance is one of the methods for islanding detection. This paper presents the time-domain mathematic model for the three-phase photovoltaic grid-connected inverter. Based on this model the effects of the active and reactive current disturbances on the voltage frequency and amplitude at the point of common coupling are discussed. Quantitative analysis is also given. The islanding detection for three-phase inverter is simulated in the MATLAB/Simulink environment following IEEE Std.929—2000. The simulation results verify the theoretical analysis. The methods given in the paper are useful for minimizing the negative effect of the current disturbance on the power quality with the reliable islanding detection.