This study was to investigate the effects of fascia relaxation application on isokinetic lower extremity muscular fitness, flexibility, agility, and balance in female high school volleyball players. this study was carried out with 14 high school female players in the J. Region. Experiment 1 did not apply fascia relaxation. Experiment 2 applied fascia relaxation with a foam roller. Experiment 3 applied fascia relaxation with a massage gun. Experiment 4 applied fascia relaxation with like Strig. The experiments were conducted at an interval of two days between the experiments, and there were experiment measured knee isokinetic muscular strength, flexibility, agility, and balance in each experiment. The following conclusions were derived from the experimental results: There was significantly increased agility in Fascia relaxation therapy using a foam roller (p<.05), dynamic balance The fascia relaxation therapy using a massage gun (p<.05). In conclusion, it was found that fascia relaxation protocol before sport event had positive effects on agility and dynamic balance. Especially, the foam roller increasing load and pressure on muscles made an affect agility. The massage gun stimulating the muscles with mild vibration made an affect dynamic balance. It was judged that fascia relaxation had effects with pressure or vibration that could stimulate the muscles. For various sports players as well as volleyball players training themselves in the field, too, it is judged that it would be necessary to apply a more practical and more systematic fascia relaxation protocol to the therapy, considering peculiarities, such as sports event, time, intensity, speed, and individual difference for the prevention of injuries.