Parents are challenged to provide the required information about reproductive issues for their adolescents. The study aims to explain women’s perception of the necessity of education about adolescent girls, reproductive health to mothers. This research is a qualitative content analysis. Sampling was performed using purposeful sampling to saturation of data. The study sample included 26 mothers and 14 key informants. To collect data, semi-structured interviewing was used. Data trustworthiness was verified based on Lincoln and Guba’s criteria and the data was analyzed using conventional content analysis with MAXQDA10 software. Four themes and 13 main categories each with some subcategories were extracted in this research. The themes and categories included: “risky social-environmental factors (existence of inappropriate educational resources, a challenge between tradition and modernity in the society, social harms, and educational barriers)”, weakness in awareness, attitude, and family relationships (mother’s limited awareness, mother’s negative attitude, improper interaction between the parents and the adolescent in the family, and lack of discussion about sexual and reproductive matters in the family), problems associated with sexual and reproductive health of adolescent girls (puberty changes, insufficient perception, and understanding of the process of puberty and harms arising from early education), and high-risk behaviors of adolescents and their consequences (the adolescent’s maladaptive behaviors and their outcomes). The results of this research necessitate education of adolescent girls’ reproductive health to mothers.