Context: Different types of breathing exercises have varied effects on cardiovascular parameters and the stress levels in an individual. Aim: The aim of this study was to assess the effect of a modified form of isolated alternate nostril, slow breathing exercise on perceived stress, and cardiovascular parameters in young, male volunteers. Settings and Design: This was a randomized control study carried out at Advanced Centre for Yoga Therapy Education and Research, Department of Physiology, Jawaharlal Institute of Postgraduate Medical Education and Research, Puducherry in 2014. Subjects and Methods: Hundred healthy male volunteers were randomized into control group, n = 50 and slow breathing group (study), n = 50. Slow breathing exercise training was given to study group for 30 min a day, 5 times/week for 12 weeks, under the supervision of certified yoga trainers. Perceived Stress Scale (PSS) using Cohen's questionnaire, anthropometric parameters such as body mass index (BMI), waist-hip ratio (WHR), and cardiovascular parameters such as heart rate (HR), systolic blood pressure (SBP), and diastolic blood pressure (DBP) were recorded at baseline and after 12 weeks. The control group did not receive any intervention. Slow breathing exercise training was provided for the study group. During the study period, one volunteer opted out of the study group due to personal reasons. Results: HR, SBP, DBP, and PSS decreased significantly (P 0.05) was observed in BMI and WHR. There was no significant change in the control group. Conclusion: Twelve weeks of modified slow breathing exercise reduced perceived stress and improved the cardiovascular parameters. The above results indicate that our modified slow breathing exercise is effective in reducing stress and improving the cardiovascular parameters.