Oxygen evolution reaction (OER) plays an important role in solving energy shortage and environmental problems, but it requires a huge overpotential to overcome the slow kinetic barriers, so the development of high- efficiency electrocatalysts has become an indispensable step. In this work, the performance of α-MnO₂(001) and Mo doped α-MnO₂(001) electrocatalytic oxygen evolution reaction were studied by using density functional theory. Gibbs free energy, density of states and differential charge density were calculated according to the reaction path. The research results show that Mo doping can effectively modulate the electronic structure of α-MnO₂(001) surface, improve desorption and adsorption capacity between intermediates and the catalyst, and provide more electrons for OER. Gibbs free energy calculation results indicate that the formation of O₂ from *OOH is the rate-determining step for OER in the Mo doped α-MnO₂(001) system. Mo doping reduces the overpotential to 1.01 V, which presents a good catalytic performance for oxygen evolution.