Considering a series of problems such as voltage dip, short circuit, Gaussian noise, and harmonic output from power supplies generated by distribution networks with distributed power supplies, a method for accurately determining the position of the disturbance source is proposed to improve the power quality level. Given the topology structure and power quality monitoring information of the distributed generator distribution network, the discrete wavelet Mallat transform is used to extract the components of the high-frequency disturbance. The direction of the disturbance is judged according to the positive and negative of the high-frequency disturbance energy. At the same time, a genetic algorithm is used to set the disturbance weighting factor by using the high-frequency disturbance energy. This highlights the role of the strong signal in the positioning process, so as to accurately locate the disturbance source. The simulation results show that the method has high accuracy and good fault tolerance, and it also has guiding significance for the installation position and number of power quality monitors. This work is supported by National Natural Science Foundation of China (No. 51507157).