To address the problems of low carrying capacity and short life of bearings in current ring reducers, a new type of ring reducer is proposed which consists of a twostepped transmission. One is a planetary transmission, and the other is an Ntype planetary transmission with a low tooth number difference. Based on the analysis of structural features, the transmission principle, and a transmission load situation, a contact finite element model of the new type of ring reducer is set up, and the stress value and the actual pairs of meshing teeth are derived by calculation. Based on gear modification research theory, the second stage transmission gear pairs of the new reducer are modified on its teeth profiles. Results demonstrate that the load capacity of transmission gear pairs have been enhanced greatly.