Objective:School-based reproductive health education programs (RHEP) motivate adolescent girls to maintain and improve their health, and prevent diseases. The purpose of this PAR was to design, implement and evaluate RHEP to strengthen adolescent girl's reproductive health.Methods:The PAR process was selected as an RHEP strategy, and it has four main phases, including: 1) assessment to explore the reproductive health education needs (RHEN) of adolescent girls. We collected data through in-depth individual interviews with 11 adolescent girls (12-18 years) in high school, 2 focus group discussions (FGD), and 4 interviews with the key informants. 2) Intervention design involved a Delphi approach to design an intervention that would address each need using 7 expert participants with a background in primary health, health promotion and other youth-focused professions. 3) In the action plan phase, the workshops, lecture meetings, counseling, and FGD were organized by the research team. 4) The impact of the intervention was evaluated through a mixed evaluation methodology, a semi-structured interviews with stakeholders and key informant, quasi-experimental assessment and FGD.Results:There were three themes we extracted from the data: (a) the need for RHP for adolescent girls, (b) sources of information about RH, and (c) the need to empower teachers to provide RHEP to their students. a) Workshops, (b Counseling, c) Lecture Meetings, d) Focus Group. The study showed that the level of knowledge about RH in more than half of the participants was poor and only in nearly half of them it was moderate.Conclusion:Results suggest that Iranian adolescents do not have adequate education regarding RH, and RHEP by PAR can be effective in improving the knowledge and behavior of female students.