Background: Prehypertension predicts established hypertension. The structural and functional alteration of the heart caused by prehypertension is unclear. Aims and Objectives: The present study was designed to compare the diastolic function in young normotensive and prehypertensive subjects between the age group of 18__ampersandsignndash;35 years. Subjects and Methods: Pulse wave transmitral Doppler echocardiographic data was assessed in 100 subjects. Of which, 50 were normotensives (systolic __ampersandsignlt;120 mm Hg and diastolic __ampersandsignlt;80 mm Hg) and 50 were prehypertensives (systolic = 120 __ampersandsignndash; 139 mm Hg and diastolic = 80 __ampersandsignndash; 89 mm Hg). Their early and late diastolic peak mitral flow velocity ratio (E/A ratio) were measured. Un-paired student__ampersandsignrsquo;s t-test was used for statistical analysis. Results: When compared with normotensive, in the prehypertensive group the E/A ratio was significantly decreased (p=0.05) Conclusion: This study concludes that diastolic abnormalities starts even in young prehypertensive individuals. The changes in the indices of diastolic function were only subtle in this age group of prehypertensives. Prehypertension is a predictor of established hypertension and diastolic dysfunction.