The work aims to understand the load distribution of the RV transmission mechanism and study the system’s mechanical properties. First of all, the structure of type 2K-V RV transmission system for precision robot and the characteristics of RV transmission were briefly introduced and analyzed. The stress situation of the external gearing planetary transmission mechanism and the internal gearing cycloid-pin wheel transmission mechanism in RV transmission were lucubrated respectively. In addition, the initial meshing clearance, the multi-tooth meshing principle and the force of the crankshaft rotary arm bearing were considered. The selection of the short-amplitude coefficient K1 was directly related to the force of the cycloidal gear, the meshing force between the cycloid gear teeth and the pin gear was linearly proportional to the actual elastic deformation of the cycloid gear teeth at the meshing point. RV transmission system has a wide application prospect in robot field, and the research on mechanical properties provides a theoretical basis for the accuracy design, manufacturing and processing of RV transmission mechanism.