This paper presents a Super Twisting Algorithm (STA) based Sliding Mode Control (SMC) method for 9-Level Packed E-Cell (PEC) inverters. Firstly, the mathematical background of the PEC inverter is presented. Then, an objective function was defined for the regulation of inverter output voltage. SMC method is designed using the objective function. Finally, STA and SMC methods are integrated to eliminate the chattering effect. The effectiveness of the control algorithm was investigated by simulation studies.