Introduction:                 Mitral valve area (MVA) is related to body surface area (BSA) of an individual and so it varies among individuals of different ethnic origin. We have calculated mitral valve area per square metre of body surface area in cohort of 50 patients who underwent percutaneous balloon mitral valvotomy (PBMV) at our centre both pre and post procedure. This data is then analyzed and compared to various studies across other parts of India and world. Objectives: –          To calculate BSA of patients undergoing PBMV –          To assess MVA per square metre of BSA of an individual pre and post PBMV Methodology: This observational study was a cohort of 50 patients who satisfied ACC/AHA class I indication for PBMV over period of 1 year from Nov, 2014 to Nov, 2015. MVA was calculated a day prior and 2 days after the procedure with planimetry on 2D echocardiography. BSA was calculated using Du Bois method where BSA = 0.007184 × height0.725 × weight0.425. Observation: The study population comprised of 41 female and 9 male patients, out which 42 were in normal sinus rhythm. Mean BSA of population was 1.36 m2 with standard deviation (SD) of 1.34. Pre PBMV MVA mean was 0.59 cm2/m2 of BSA with SD of 0.12. Post PBMV MVA mean increased to 1.15 cm2/m2 of BSA with SD of 0.19(t=–19.7, df–49, p<0.0001). Simultaneously left atrial pressures (LAP) were recorded pre and post procedure as measure of success of procedure. Mean LAP of 23.58 mmHg with SD of 7.70 dropped down to 11.56 mmHg with SD of 4.84(t=10.32, df–49, p<0.0001). When compared to studies in other part of country and world, pre BMV MVA varied across different region depending upon the which ethnic population was studied. Conclusion:                 MVA per BSA might standardize the cut off values across different ethnic population and provide more comparable data not only for PBMV but also other procedures dealing with mitral valve.