The purposes of this study were to measure skin temperature and blood flow on the contralateral upper extremity when heat is applied to one upper extremity, were to compare the effect of contrast bath. The subjects were 38 healthy adults with no history of peripheral vascular disease. The subjects of contrast bath were 18 persons and the subjects of warm bath were 20 persons. The subjects of one group were seated with their right arm in water($42^{circ}C$) up to the mid-forearm. The subjects of the other group were seated with their right arm up to the mid-forearm in water which was changed from warm to cold using the contrast bath technique. The continually changing temperatures and blood flow were measured by an independent observer at intervals of 10, 15, 20, 25 and 30 minutes respectively after the start of the procedure. The results were as follows. The temperature of the warm bath group rose 4.28% over the pre-experimental temperatures and the temperature of the contrast bath group rose 3.41%. There was no statistically significant difference between the two groups. The blood flow of the warm bath group rose 8.31% over the pre-experimental blood flow and the blood flow of the contrast bath group rose 17.24%. There was a statistically significant between the two groups 20 minutes after the start of the procedure. Thus the contrast bath is a more effective method than the warm bath to increase blood flow.