Abstract: With the widespread use of distributed generation, a large number of power electronic switches and nonlinear loads greatly deteriorate the power quality of the microgrid. In order to effectively address harmonics problems in the microgrid, a novel control strategy of the unified power quality conditioner based on photovoltaic grid-connected generation and supercapacitor energy storage (SCPV-UPQC) is proposed in this paper. The control system is able to calculate the compensation amount and send an appropriate control signal by extracting the fundamental and harmonic components in the current and voltage signals of the PCC point. And a fuzzy control method is proposed to adaptively adjust the parameters of the traditional PI controller to mitigate the harmonics and other power quality problems of microgrid. The proposed SCPV-UPQC structure based on the fuzzy PI control strategy is simulated in MATLAB/Simulink under a typical microgrid model, and the results illustrate that this method can significantly suppress the harmonics in the microgrid, verifying the validity and feasibility of the proposed UPQC structure and control strategy. The method can provide helpful assistance for harmonic control of the future AC or DC microgrid and even multiple parallel microgrids.