Abstract: In view of the problems existed in traditional photovoltaic grid-connected power system such as low output voltage, big fluctuation range, high energy consumption and bad reliability, the paper proposed a design scheme of Z-source photovoltaic grid-connected inverter based on one-cycle control. It analyzed circuit structure and characteristics of Z-source inverter, introduced implementation of one-cycle control strategy of Z-source inverter in details, and built simulation model with Matlab/Simulink. The experiment result showed that the Z-source inverter has good boost effect which reduces requirement of photovoltaic cells' voltage level, and using one-cycle control technology can track network voltage well which realizes unity power factor.