The increasing use of power-electronics equipment has led to various power quality problems, including current wave distortion . Also, renewable energies (solar and wind energy ) are increasingly used to supply part of the electrical load,especially Photovoltaic (PV). The use of PV-STATCOM achieves many benefits, among them mitigating the distortion of the current wave , improving the power factor , compensatingthe active and reactive power , and improving the system 's stability. This paper deals with mitigating current wave distortion and improving power factors together. This paper designs a STATCOM Modular Multilevel Converter (MMC) controller with combines reactive power compensation and harmonicsmitigation for linear load and proposed a simulated six pulse three-phase rectifier as nonlinear load. The pulses gate of theswitches of the sub -modular converter has been obtained by using a proportional -integral (PI) current controller with d-q references. The time-domain-based reference method for the reference current extraction is adopted. MMCSTATCOM were simulated with proposed nonlinear model loads in MATLAB . The simulation result showed that the developed MMCSTATCOM minimizes the total harmonic distortion below the standards recommended by the IEEE.