LCL filter, which can reduce the required filtered inductance and save the cost, is adopted in the three-phase gridconnected photovoltaic system. However, systems with LCL filter need more complex control strategies. This paper analyzes a twoloop control method which uses the capacitor current and grid current as the inner and outer control variable respectively. Detailed discussions about the role of the loops and the influence on the system caused by every parameter of the controller are given out. Finally experimental results verify the correctness of the analysis and availability of the control strategy.Keywords: LCL filter, two-loop control, capacitor current, grid current