Tobacco is a product from agriculture, which is commonly consumed as a recreational drug. Tobacco consumption is a worldwide problem among the adolescents. In India the annual incidence of oral cancer among men is estimated to be 10 per 10000 population. In India tobacco consumption is responsible for half of all the cancers in men and a quarter of all cancers in women, in addition to being a risk factor for cardiovascular disease and chronic obstructive pulmonary diseases. The present study aim to assess the knowledge on ill effects of tobacco consumption and its prevention among adolescents in selected inter colleges at Mandhana, Kanpur Cross sectional survey approach with simple descriptive research design was used in the study