This research is to study the development of teenagers’ psychology, comprehend the concept of sex education in Islam based on Syrah An-Nur verses 30-31 and find the methods of sex education in Islam based on Syrah An-Nur verses 30-31. The type of the research in this undergraduate thesis is a library research, using books as the sources of data with a descriptive qualitative approach. The research methodology is a documentation using psychology and fiqh approaches. The types of data in this research are primary and secondary data. The former ones were taken from a book written by Hannan Atiyah At-Turi entitled Mendidik Anak Perempuan di Masa Remaja, whereas the latter was taken from books and journals related to methods of sex education for teenagers in Islam. After gathering the data, the researcher analyzed the data in 3 stages: (1) Data reduction, by searching data through literature review, (2) Data presentation, by collecting the data, (3) Conclusion. The conclusion of the study showed that the teenagers’ psychological development include (1) the teenagers’ self concept development, (2) Emotion, (3) Interest/Ambition, (4) Social interaction, (5) Intellectual/cognitive development. In addition, the concept of sex education in Islam based on Surah An-Nur verses 30-3, namely (1) Lowering the gaze, (2) Protecting private parts, (3) Avoiding tabarruj (exposure of beauty). The four approaches of sex education in Islam based on Surah An- Nur verses 30-31 are (1) Habitual approach, (2) Exemplary approach (3) Dialogue approach, and (4) Supervision approach.