Background: Premenstrual syndrome is said to be a psycho neuro endocrine disorder with biological , psychological components along with stress as a major cause.. Yoga is a unique method for balancing two components of autonomic nervous system & influencing psychological & stress related disorders . Objective: To assess and compare the effect of 61 - point relaxation technique on systolic BP, diastolic BP, Heart Rate & Respiratory Rate in patients of PMS before and after intervention and compare the effect of 61 - point relaxation technique on SBP, DBP & Heart Rate in persons with and without premenstrual syndrome . Method: A total number of Sixty women in reproductive age group were studied in premenstrual phase of menstrual cycle . Cold pressor test was used to assess sympathetic activity . Basal parameters including systolic BP , diastolic BP , heart rate and respiratory rate were recorded before & after cold pressor test in both control & study group before & after 61- point relaxation technique . Results: Basal SBP, DBP and RR of females with premenstrual syndrome was significantly higher than the control subjects suggesting the presence of stress in females with premenstrual syndrome. Immediately after cold pressor test, the said parameters were statistically significantly more raised in premenstrual syndrome group than control group respectively. Following 1 week of 61-point relaxation technique training , the control group showed a significant decline in systolic blood pressure, diastolic blood pressure heart rate and respiratory rate respectively. However, the premenstrual syndrome group showed a statistically highly significant reduction in systolic blood pressure, diastolic blood pressure , heart rate and respiratory r ate immediately after cold pressor test. Conclusion: These results depicts a decline in sympathetic activity by 61- point relaxation training and it can be used as an efficient relaxation tool to reduce the premenstrual stress .