Background: Obesity is a serious health problem and its prevalence has increased dramatically over the past 20 years [1].If current trends continue 2.7 billion adults will be overweight by 2025 from 2.0 billion in 2014. On current trends, 177 million adults worldwide will be severely obese and in need of treatment by 2025 [2].Overweight and obesity are defined as abnormal or excessive fat accumulation that may impair health. Body mass index (BMI) is a simple index of weight­forheight that is commonly used to classify overweight and obesity in adults [3]. Objectives: To assess the knowledge regarding life style modification related to obesity among adolescents. To assess the attitude regarding life style modification related to obesity. To determine the relationship between knowledge and attitude of adolescents students regarding life style modification related to obesity. To find out the association between knowledge and attitude of Adolescents with selected socio­ emographic variables. Methodes: A descriptive study involving 100 adolescents was self administered questionnaire. Data were collected by using systematic random sampling technique. It included data regarding socio­demographic characteristics and questions pertaining to knowledge and attitude regarding life style modification related to obesity. Results: Out of 100 adolescents, it was seen that 54 per cent adolelescents had moderate knowledge about lifestyle modification related to obesity , 41 per cent adolescents had moderate level attitude about life style modification related to obesity. Conclusion: The knowledge and attitude regarding the life style modification related to obesity is moderate. So, there is need to educate adolescents regarding life style modification about obesity as well as dietary pattern, exescises to reduce the obesity .