This study entitled ''knowledgwand awareness on HIV / AIDS among high school students'' concludes the level of awareness on HIV / AIDS as HIV / AIDS being one of the great problems in a poor country like Nepal but the result shows moderately aware populations in the case of school students. Study focused on teenagers because this age group is considered as a vulnerable age group. We know that ‘prevention is better than cure’. On the matter of HIV/AIDS there is nothing to be done except prevention.