An optimization model is constructed to formulate the maximization problem on the capacity of V-belt drive. The concavity,the monotonicity and the global optimality condition are studied for the objective function,and it is proved that the feasible region of the model is bounded,closed and convex under some design conditions. Then,a solution method,called an optimal segment algorithm,is developed to find the global maximizer of the model. Under four different design conditions,solution methods are presented respectively. Some real case studies are employed to demonstrate that the model and the algorithm in this paper are promising. An optimization model is constructed to formulate the maximization problem on the capacity of V-belt drive. The concavity, the monotonicity and the global optimality condition are studied for the objective function, and it is proved that the feasible region of the model is bounded, Then, a solution method, called an optimal segment algorithm, is developed to find the global maximizer of the model. Under four different design conditions, solution methods are presented respectively. Some real case studies are employed to demonstrate that the model and the algorithm in this paper are promising.