In Five-axis machine tools, rotary table is often used as a means for providing rotational motion and is responsible for supporting and rotating the work-piece. Its rigidity, precision and carrying capacity is directly related to the machining ability and the accuracy of NC machine tool. Traditional rotary table design is normally performed by teams, each with expertise in a specific discipline, which cause excessive iterations and cannot provide users with reliable working performance and bearing capacity products. To achieve an optimal design with less cost and better performance, this paper considers the mutual interaction of hydrostatics and structure disciplines involved in the design of hydrostatic rotary table, and a sensitivity-based multidisciplinary optimal design procedure of hydrostatic rotary table is proposed. Sensitivity analysis is adopted to identify the key design parameters which have major influence on the performance of rotary table to improve the convergence. The constrained multi-objective optimization problem is solved by using particle swarm optimization approach. A hydrostatic rotary table of a five-axis heavy duty machine tool is selected as an illustration example. The results show that the proposed method can realize the multidisciplinary optimization with a result of satisfied rotary table of good rigidity and bearing capacity.