The purpose of this study was to compare the differences of upper limb isokinetic peak strength between high and general serve velocity in female tennis players. Twenty female collegiate tennis players were volunteered in this study. All participants were equally assigned into high serve velocity players (HP, velocity in serve=145.40 ± 5.6 km/h) and general serve velocity players (GP, velocity in serve=128.30 ± 5.31 km/h) based on the performance of speed in serve. Isokinetic strength tests were performed by the Biodex S4 dynamometer for dominant shoulder flexion/extension, shoulder 90° abduction external/internal rotation, elbow flexion/extension, and wrist flexion/extension at three different angular velocities. Independent t-tests were used to analyze the different of isokinetic peak torque per body weigth (PT/BW) at each angular velocity between groups. Result showed that: 1. HP showed significant higher PT/BW in elbow extension at 120 deg/sec, 240 deg/sec and 360 deg/sec angular velocities. (t=3.48, 3.33, 2.39; p<.05). 2. No significant differences were found in shoulder flexion/extension, shoulder 90° abduction external/internal rotation, elbow flexion, and wrist flexion/extension isokinetic PT/BW between groups in each testing. From these results, this study demonstrated that strength in elbow extension may play an important role for the tennis serve velocity. Therefore, it is recommended that tennis training should strengthen the elbow extension to improve the serving velocity.