Traditional multilevel inverter circuit structure and control principle are complex and high cost to realize, and it is not suitable for small power inverter applications. A multilevel inverter is designed for small and medium-sized power applications. The voltage waveform for multi-level inverter requirement is obtained through the combination of converter technology and the reasonable control of PWM. The principle and design method of multilevel inverter are introduced, the circuit structure of the system is presented, and the scheme is simulated by Multisim11.0. The simulation results show that by means of controlling the given voltage to realize multilevel inverter, the output voltage waveform can better follow the given and the control method is simple.