Introduction: Premarital sex behavior among teenagers tends to increase. This study aimed to describe adolescent perception of premarital sex behavior. Methods: This research used a quantitative design with a descriptive ap- proach. The variable in this study is the perception of premarital sex behavior. The population were 72 adolescents aged 10-24 years and unmarried. This study used a total sampling technique and a questionnaire instrument about perception of premarital sex behavior that have been tested for validity and reliability. This study conducted a de- scriptive statistical analysis. Results: The results showed that nearly 60% of participants had negative perception of premarital sex behavior. This happens because of the influence of knowledge and level of education, the influence of the environment, and the economic conditions of the family. Conclusion: These various perceptions raise the urgency of nurses to be able to play an active role in providing reproductive health education and the education of the impact of premarital sex behavior for adolescents in Indonesia.