The purpose of this study is to examine the effect of Prunus mume supplementation on changes of energy substrate (glucose, FFA) and fatigue factors (lactate, ammonia, phosphorous) in the performance of exercise. The subjects of this study were 15 male university students. The exercise test was performed for 30 minutes at 75% VO2max on the treadmill and conducted both before and after administering Prunus mume for 6 weeks. Through Prunus mume supplemntation, the accumulation of such fatigue factors as lactate, ammonia, and phosphorous along with concentration of glucuse decreased, but the concentration of FFA increased. From the study, it can be seen that Prunus mume plays a positive role for the use of energy substrates and accumulated fatigue factors.