Background: The era is getting more advanced by following the development of the world globally, likewise the development of drugs is getting more intense, so to save the future of the nation, teenagers, especially high school students, really need to increase their knowledge about the dangers of drug abuse. The influence of changing times from year to year always affects life for everyone, especially the negative influence on adolescents, because adolescents do not yet have stable independence. Based on current observations, many high school children smoke both at school and outside of school, considering that smoking together with peers is one way to use In this era, drug sellers have entered villages looking for target buyers from both the community and school children since elementary school, junior high school and high school, because the seller is good at selling by mixing it with food, premen or what is still used. pure then for the teacher or or Parents must be observant in supervising children in social and change. Objective: To find out the effect of giving drug material on increasing the knowledge of high school students about drugs and their prevention. Method: the method used in this research is descriptive analytic with the approach used is cross sectional. Sampling used with total sampling and test analysis using Chi Square tes. Results: Based on the characteristics, it was found that the age of the respondents was between 15-20 years old with the most results being 16 at 50.6% and 17 years, namely 40.6%, for parent education the majority of basic education was 66.2%, Respondents' parents were traders and entrepreneurs of 40.26%. For the level of knowledge, the majority of the good categories were 73.4%. so that there is an increase in the level of knowledge about drugs. Conclusion: There is an effect of giving drug material to increase respondent's knowledge