Internal gearing power honing (IGPH) process constitutes a crucial process in the manufacturing of high-performance transmission gears for new energy vehicles and other equipment. Mastering and enhancing the residual stress distribution on the IGPH gear tooth surface serves as an important means to ensure the outstanding meshing performance of transmission gears, such as high strength and long service life. Considering the contact characteristics between the tooth surface of work-piece gear and honing wheel, founded on the basic theory of staggered-axis spatial conjugate internal meshing, the honing speed of the abrasive grain of the honing wheel relative to the tooth surface of the work-piece gear and the model of the honing force were acquired. Subsequently, theoretical analyses of the mechanical and thermal stresses during honing were conducted, and the model of the distribution of the IGPH gear tooth surface residual stresses was further established. Taking 20CrMnTi hardened gears as an example of commonly used new energy vehicle gear reducer gear material to carry out the IGPH process test, the rationality of stress which is left over distribution model of the surface of the tooth of the IGPH workpiece gear was verified. The outcomes of several sets of comparative tests indicated that the proposed method could effectively predict the distribution law of residual stress on the tooth surface of the IGPH workpiece gear, which can provide guidance for stabilizing the quality of stress which is left over on the IGPH gear surface of the tooth with variable axial intersection angle.