For the design of tennis racket, finite element analysis using a realistic model is the most powerful tool. Total analysis system based on finite element method for the ball-racket impact without ball-spin has been developed. Improvement of the standard tennis racket in order to increase its coefficient of restitution is performed by using the developed system. Effects of changes of stiffiness, mass and string pattern for the racket are investigated. It is found that the optimal arrangement of frame mass is effective for the up of restitution performance of racket. Finally, an example of the improved racket is presented and its higher performance is verified. From present analysis, the applicability of the developed system to the optimal racket design is demonstrated.