Abstract: In order to improve the stability of photovoltaic grid connected system in weak grid,a compound control strategy based on common coupling voltage frequency-selecting feedforward and phase lead compensation is proposed in the paper. In this strategy,frequency-selecting is designed to improve the feedforward function of grid voltage. It can not only keep the suppression of background harmonics,but also avoid the sharp decrease of stability margin. And it is proposed that the phase-leading link is added to the current path to compensate the decrease of phase angle margin caused by the impedance of weak grid and increase the stability margin. The effectiveness and feasibility of the strategy are verified by the simulation and the experiment.