This paper presents a comprehensive investigation into the total harmonic distortion (THD) of cascaded H-bridge multilevel inverters when employing different pulse width modulation (PWM) techniques. They produce the high-quality output waveform with reduced THD, and due to this advantage, multilevel inverter gained the significant attention in recent years. The output waveforms are generated in staircase current or voltage form. The MLI has contain number of advantages, such as it avoids the filters because the harmonic content is less at higher levels, they do not require any clamping diode and flying capacitors then to control the CHB MLI is very convenient, so weight and cost of CHB inverter is less than others MLIs. The paper has done the analysis of variation of total harmonic distortion of single-phase cascaded H-bridge multilevel inverter and also the performance of the inverter using different pulse width modulation techniques such as alternate phase opposite disposition technique, phase disposition, and phase disposition by using the MATLAB simulink software.