The purpose of this paper was to compare the isokinetic muscular strengths, endurance, and power of thigh and shoulder between volleyball players and elementary school boys. The isokinetic strength was investigated by using isokinetic dynamometer(Cybex 770, NormTM Test & Rehabilitation, USA). For measuring the peak torque, muscle power, and muscular endurance, extension and flexion forces of knee and shoulder joints with both right and left sides were measured at the angle speed of 60°/sec(4 repetitions), 180°/sec(4 repetitions), and 240°/sec(5 repetitions), respectively. The mean and standard deviation are evaluated over the data measured by using SPSS program, and Independent t-test was used for validating the mean difference between each variables. The level of significance was set as α = 0.05. The thigh strength and power in extension and flexion were not significantly different between volleyball players and elementary boys, respectively. However, the thigh endurance of extension and flexion in volleyball players was significantly greater than in elementary boys (p < 0.05). The shoulder extension strength and power in the volleyball players was significantly greater than in elementary boys(p < 0.05). Also, the shoulder extension and flexion endurances in volleyball players were greater than in elementary boys(p < 0.05). Therefore, the recreational volleyball activity in elementary school might be recommended to enhance the fitness-related muscular endurance ※ Key Words : isokinetic, muscle strength, volleyball player