Harmonic on a power system refers to the voltages and currents imposed on a system that has frequencies which are a multiple of the fundamental frequency. It is the main index and the most important parameters of power quality. Harmonics generated by nonlinear loads cause harmonic pollution. Because this pollution can cause problems within power systems that can range from the false operation of protection devices to the physical damage of power system components and loads, it is urgent to eliminate harmonics. First, this paper lists a variety of harmonic sources and their impact on the power system. Second, based on the harmonic pollution characteristics, this paper suggests some management remedies for harmonic problems.