The purpose of the study was to examine the effect of ingestion of water or glycerol on renin activity, rectum temperature, blood electrolytes concentration in exercise. The present study took as its subjects five male students who major in physical education. The two different conditions were based on ingestion of water, ingestion of glycerol and a series of four blood gatherings were carried out at rest, at post-exercise 20 min, at post-exercise 40 min, at recovery. The findings of this study was as follows; On renin activity change, in the comparison within at rest ingestion of glycerol, ingestion of water were significant difference at post-exercise 20, 40 min (p<0.01). 2. On osmolality change, in the comparison within at rest, ingestion of glycerol was significant difference at post-exercise 40 min (p<0.05). ingestion of water was not. On Na and K concentration change, in the comparison within at rest, ingestion of glycerol was significant difference at post-exercise 40 min (p<0.05), ingestion of water was not. On Ca and Mg change, in the comparison within at rest, ingestion of glycerol, ingestion of water were no significant difference at all period.