Microgrid voltage quality is related to the distributed generation (DG) interfacing inverters (DGI), especially in the islanded mode. To improve the point of common coupling (PCC) voltage quality, a high voltage quality control strategy has been proposed for the microgrid main inverter (MMI) which operates as a voltage source in the islanded microgrid. Firstly, the harmonics degradation mechanism of inverters-based microgrid is analyzed. And it can be found that the PCC voltage quality will be distorted when DG interfacing inverters work without voltage quality control loop. Then, the harmonic voltage control principle of MMI is shown, and the computation load, signal sampling and capacity limitation are considered. Finally, the validity of proposed control strategy has been proven by the simulation and experimental results.