The average current control method of the traditional interleaved parallel Boost PFC circuit is based on current sharing control, but in practical applications, it is impossible to ensure that the parameters of the components are consistent, and the current sharing control cannot be realized. In view of the above problems, a duty ratio method is proposed to realize the current sharing of interleaved parallel boost PFC. In this method, 1 / 2 of the average total inductance current is compared with the average inductance current of each phase, and the duty ratio of each phase is determined according to the comparison results. The design of 400V / 200W interleaved parallel PFC power supply is realized by calculating the parameters of each component of the circuit. Finally, Matlab is used to verify the simulation. The simulation results show that the proposed method can achieve high input power factor and current sharing of two inductors.