Background: Hypertension among school going adolescents as an evolving public health concern in urban India is well recognized. In the present study, an attempt was made to find the prevalence of hypertension among school attending adolescents in 11-19 years age group and to study the socio-demographic, and life style habits prevalent in this study group contributing to hypertension in this study group. Materials and Methods: Descriptive, cross-sectional study was conducted during September 2012 to January 2013 in secondary and matriculation schools in sub-urban parts of Rathinamangalam, Kancheepuram District. A total of 1540 students were randomly selected from six schools in the study area and purposive sampling of adolescents is done for the operational feasibility. Blood pressure readings along with socio-demographic and life-style characteristics were recorded using a pre-tested questionnaire. Results: Among 1540 students, the prevalence of hypertension (>95 percentile distribution per age and gender) among male adolescents in this study is 1.9% and 1.72% among female adolescents. The prevalence of isolated systolic hypertension (>95 percentile distribution per age and gender) among males is 0.71% when compared with 0.28% in females. Conclusion: Prevalence of hypertension is found to be less but life style factors, which can have negative effect on blood pressure, are highly prevalent. Preventive efforts should target school attending adolescents to promote healthy life styles habits.