Among the systems for repairing the ship, the turning gear is functionally designed with the durability life of the ship along with the durability of the ship, and it is necessary to design the product which satisfies both wear resistance and durability. Based on the basic design theory of gears, we developed the analysis technique of turning gears. The gear tooth profile was modeled on the multibody dynamics of a system composed of planetary gear train using RecurDyn of FunctionBay. Flexible multibody dynamcis analysis was applied by applying a finite element model to the shaft, which was expected to be based on theoretical formula, and the durability evaluation was performed.