BACKGROUNDKidney function and hypertension are closely linked. What is the prevalence of hypertension and how one is affecting the other? Different studies show different results. Such a study in Keralite population is planned.The objectives of the study are to find the prevalence of hypertension and prehypertension in a population of Kerala and its effect on GFR. MATERIALS AND METHODSA total of 519 subjects of all ages from the community are screened. Blood pressure and serum creatinine were assessed. e-GFR found using MDRD (modification of diet in renal disease) formula. RESULTSPrevalence of hypertension in the study population is 13.9% and prehypertension is 26.8%. Incidence of hypertension is increasing with age. Estimated GFR showed a decrease in hypertensives and prehypertensives. CONCLUSIONKidney function is affected by an increase in blood pressure.