The increasing number of non-linear loads causes a severe harmonic problem in low voltage power network. The distributed generations (DGs) not only integrate renewable energy sources into utilities, but also provide an effective way for harmonic suppression. Based on the different wiring modes of three-phase asymmetric load, a harmonic compensation control method using single-phase DGs is presented. Firstly, the wiring modes and load conditions of typical harmonic source are analyzed. By equalizing the asymmetric load into star with or without neutral line and delta wiring modes, the distribution of the harmonic current is discussed and the harmonic compensation function is derived. On the basis, the harmonic component of each phase load and circuit is extracted depending on the time delay and synchronous frame transform, and the harmonic compensation control scheme of single-phase DGs is established. Finally, the simulation results verify the effectiveness of the presented method to harmonic suppression by means of Matlab/Simulink. This work is supported by National Natural Science Foundation of China (No. 51577018).