This paper presents a novel three-phase boost flying capacitor three-level inverter topology. Compared with the traditional H-bridge buck inverter, this topology can realize step-up inverter without the previous step-up circuit, and can be applied to the step-up inverter occasions. The topology is simple, and there is no leakage current at both ends of the converter. The converter can be applied to photovoltaic inverter, and there is no leakage current while realizing step-up inverter, so it has a broad application scenario and application value. This paper analyzes the working principle and working mode of the topology, which are simulated and verified by Simulink.