This paper aims to present a control scheme based upon Particle Swarm Optimization (PSO) algorithm in order to compensate the key power-quality disturbances, particularly voltage sags and harmonic voltages, using a Dynamic Voltage Restorer (DVR). According to the aforesaid method, DVR's PI controller structure is regulated via multi-objective PSO algorithm. We introduce the method for distribution systems to modify both SAG and THD as major power quality indices in sensitive loads at fault conditions. Therefore, we apply the multi-objective optimization algorithm in order to attain a better performance in solving the related problems.