Adolescence is a period of transition from child to adult, this period is often referred to as the critical period, where there is physical, psychological, sexual and intellectual growth, and the start of exploration of matters relating to sexual and romanticism. According to WHO, adolescents are aged 10-19 years. During the COVID-19 pandemic, students are still studying online at home. There are several things related to adolescent reproductive health that must be conveyed to students because Harapan Mulya Brangsong Vocational School is a vocational vocational school that has very little knowledge about adolescent reproductive health, misinformation that they get from social media can plunge students into negative sexual behavior. Based on the results of the Indonesian Demographic Health Survey (IDHS) in 2017, about 33.3% of female adolescents and 34.5% of male adolescents aged 15-19 years were at risk of risky sexual behavior. The purpose of the activity is to increase students' knowledge related to reproductive health. The activities carried out were in the form of counseling, discussion and question and answer using slides from Power point (ppt) and playing an explanation video about HIV AIDS risk factors that were shared in the whatsapp group and then questions and answers were carried out via wa group chat. The result of this activity was that 60 participants from class X to class XII saw an increase in students' knowledge about adolescent reproductive health during the Covid 19 pandemic, namely the mean pre test value of 40.98 increased with the mean post test value of 86.50.