Introduction: Hypertension is a common non communicable disease in developed countries. But nowadays even in developing countries like India its prevalence is increasing in adults as well as in childhood population. Objective: To find out the prevalence of Pre hypertension and Hypertension amongst school children and adolescents. Study Design: Randomised, Cross-sectional, observational multicentric School based study. Methodology: In this study 3 schools were selected by simple random sampling method from Urban and rural region of Bijapur district which is a part of North Karnataka. Total 2800 children were screened in the age group from 10-16 years. General data and Blood pressure were recorded for each child. Blood pressure values are compared with reference charts given by National High Blood Pressure Education Programme working group of American heart association 2004 and grouped as prehypertensive (PHTN) and Hypertension (HTN). Results: In Rural school children, Prevalence of systolic PHTN was 2.2% and prevalence of systolic HTN was 1.8%. Among urban school children prevalence of systolic PHTN was 3.92% and prevalence of systolic HTN was 3.79%. Prevalence Diastolic PHTN in rural school children was 2% and that of Diastolic HTN was 1.5%. In case of urban school children, the prevalence of Diastolic PHTN was 4.28% and that of Diastolic HTN was 3.86%. In our study the prevalence of hypertension in males was more than female in both rural & urban school children. Also the prevalence of HT was more in urban than in rural population. Conclusions: Prevalence of hypertension in school children is increasing even in developing countries. In feature to prevent morbidities, early intervention strategies for promoting healthy eating, physical activities and health education should be undertaken from school age group. This primordial prevention should be considered as an important public health issue in our developing country.