An improved particle swarm optimization algorithm is proposed, which the particle swarm optimization algorithm is revised and asynchronous time-varying acceleration coefficients and linear weight coefficients are introduced. It takes the harmonic distortion, capacity of reactive power compensation and the original investment as optimal objectives and uses improved particle swarm optimization algorithm for the design of the PPF parameters of hybrid active power filter. Simulation result verifies the theoretical analysis and the design, and the related design method can provide reference for PPF design of other types of HAPF.