Abstract: With the accelerating process of urbanization, the people's demand for power energy is gradually increasing. We should strengthen the management of power system and meet the actual needs after adopting corresponding relay protection measures. Based on this, this paper first briefly explains the principles that should be followed in the fault treatment of distribution network, introduces the main problems existing in the fault treatment of relay protection of distribution network automation combined with the actual situation, and puts forward the cooperative application of relay protection and distribution automation. After putting forward improvement measures for the cooperative application, it provides a certain theoretical basis for improving the operation quality of power grid.