Background: Cardiovascular disease is an umbrella term used for all conditions that affect the heart and blood vessels. The younger population is often unaware that they may be at risk and may fail to take the appropriate actions that could save their lives. Materials and Methods: An Pre experimental study was conducted to find out the effectiveness of structured teaching programme on knowledge regarding healthy lifestyle to prevent cardiovascular disease among adolescents. On 1st day pretest was done by using structured questionnaire and on same day structured teaching programme was conducted for the adolescents regarding how to maintain a good and healthy life style and how we can prevent cardiovascular diseases. On 8th day posttest was taken. Result: It has been found that the majority of adolescents have inadequate knowledge regarding how healthy lifestyle can be maintained and how we prevent cardiovascular diseases. In pretest 93% adolescents had inadequate knowledge, after structured teaching programme in posttest 72% adolescents have adequate knowledge regarding healthy life style to prevent cardiovascular diseases. The mean difference of pre-test and post-test knowledge score was statistically significant (t100= 19.23 which was higher than tabulated 't' value 1.98 at 0.05 level of significance) Conclusion: The Structured Teaching Programme was effective method of imparting knowledge to adolescents.