The issue of power quality in the distribution system is always in sense of the concern. With the high penetration of distributed generation (DG) currently, it tends to be more complicated. This paper presents a new approach to evaluate impacts of the DG on power quality of the distribution network. In the process an objective function will be modeled, which will be solved by the optimization toolbox, in order to calculate the result for the evaluating grade. Furthermore, the results of the overall evaluation will be given via the eigenvalue weighted method. The power quality ranking of each feeder with the distributed generators in the distribution network will be apparent with the given weight of influence caused by DGs divided in forms of energy resource.