The purpose of this study was to identify how relaxation therapy affects physiological and subjective responses related to laboratory pain. Twelve female nursing students were conveniently selected those who agreed to the experiment and have no physical problem. The research method was to measure physiological change and subjective intensity of pain before and after applying relaxation while laboratory pain(cold pressor) was present. The instruments used for this study are follows. EKG monitoring was used for measuring their heart rate and blood pressure among the responses of the autonomic nerve system. Visual Analogy Scale (VAS) for subjective evaluation, and a stopwatch was used for the cold pressor pain threshold(the time from immersion to first pain sensation) and tolerance(the time from immersion to withdrawal of the arm from cold water). VAS was linear, horizontal, and 100mm long. The extremes were "no pain at all(0mm)" and "maximum pain you can imagine(100mm)". The collected data were analyzed descriptive statistics and paired t-test by using SPSS PC^+. 1) The mean of tolerance time(179.83±167.36sec) after relaxation therapy was significantly longer than that of before(118.60±118.09sec)(t=-2.59, p=.025) The mean of threshold time after relaxation therapy was longer than that of before, but the statistical differences were not significantly shown. 2) While the subjects reported cold pressor pain threshold, the mean of heart rate(78.08±9.30/min) after relaxation decreased significantly than that of before (83.83±7.78/min)(t=3.07. p=.011). 3) The changes of blood pressure between before and after relaxation were not significantly shown. 4) After applying the relaxation, degree of pain during the cold pressor by suing a VAS decreased than that of before, but the statistical differences were not significantly shown. In conclusion, by applying the relaxation therapy, heart rate was more stable, the degree of pain decreased, and the subjects can tolerate painful situation.