Background: Acquired Immuno Deficiency Syndrome (AIDS) has become the currentrnmajor public health problem in the developed and developing countries. The epidemic isrnone of the greatest challenges ever to Global well-being. Adolescents/Youthsâ€™ are amongrnthe highly affected segments of the population and their sexual behavior threatens thernphysical, psychological and social health of this group. Despite the level of knowledgernconsiderable proportions of youth are at risk of HIV infection. Hence, assessment of sexualrnbehavior among this vulnerable group is essential.rnObjectives: To assess the current sexual activity and risky sexual behavior for HIV infectionrnamong high school adolescents.rnMethods: A cross- Sectional descriptive survey was carried out among high school studentsrnin Butajira town, Meskan woreda, Gurage Zone. Data was collected by pre- tested selfrnadministered questionnaire. To complement the findings, a qualitative study was alsornconducted.rnResult: A total of 422 adolecents with a response rate of 96% for the quantitative and 36rndiscussants for the qualitative part participated in the study. Almost close to one thirdrn(29.13%) of he students was found to be currently sexually active. Among the currentlyrnsexually active respondents, 36.44% and 10.0% admitted practicing sex with multiplernsexual partners and commercial sex workers respectively. Making sexual intercourse wasrnpositively associated with sex (being male) (AOR (95% CI) = 2.68(1.49, 4.80)), pocketrnmoney (AOR (95% CI) = 2.30(1.02, 5.16)) and family income of greater than 500birr perrnmonth (AOR (95% CI) = 0.57(0.35, 0.95)). Whereas practicing sex with multiple partnerrnwas associated with alcohol drinking [AOR (95% CI) = 0.20(0.05, 0.73)], and chewingrnkhat 4.00(1.38, 11.53)].rnConclusion and recommendation: Considerable proportion of school adolescentsrnengage in risky sexual behavior. The finding also indicates that although they arernknowledgeable about HIV/AIDS, many do not practice what they know. Therefore,rnurgent health education program that aimed at bringing behavioral change of adolecentsrnshould be planned and implemented