Abstract: The suppression of common mode voltage（CMV） is critical for the non-isolated grid connected PV inverter. However, conventional zero CMV modulation method cannot guarantee CMV elimination and output current quality simultaneously. Based on the interaction between the parallel three-level inverters, the five-level voltage output capability of the parallel system is analyzed, and a novel five-level zero CMV modulation scheme utilizing only the basic vectors corresponding to zero CMV was proposed, including the detailed implementation of the modulation method. Furthermore, a neutral point voltage balancing strategy was also developed based on its specific switching sequences. Simulation and experimental results verify that the proposed method is effective to eliminate the CMV and dramatically reduce the output current harmonics compared with conventional method.