Fed by a mass of photovoltaic (PV) panels in series, the traditional buck-type flying-capacitor (FC) multilevel inverter has poor operational reliability in grid-connection application. In order to obtain a step-up output voltage, a novel five-level voltage source inverter is proposed by cascading two FC cells. The proposed inverter reduces the number of capacitors compared to the traditional buck-type topology with the same number of voltage levels. Moreover, the voltages of the capacitors can be self-balanced without using any other active-balancing strategies. Descriptions and theoretical analyses of the proposed inverter are given, followed by simulation results verifying its feasibility.