Maturity is one of the most important stages of human development, and its developmental characteristics can cause various kinds of deviations and disorders. Girls, due to their experiences of physical and mental changes, enter the stage of physical and sexual maturity earlier than boys. Their problems in the health, psychological and social dimensions are more than boys due to physiological differences, social roles and governing traditions in society. Because no research has been conducted to identify and disclose the diverse behaviors of adolescent girls, this present study is to analyze the deviant sexual behaviors of matured girls by inductive qualitative method. This research was carried out using theoretical sampling method. Up to 17 girls aged from 12 to 15 years old were purposefully sampled for the aim. In this research, the technique used for data collection was semi-structured and deep interviewing, and the grounded method (systematic: Strauss & Corbin) was used for data analysis. The analysis ultimately addresses 9 main categories including technology-driven sexual activity, risky leisure, passive self-stimulation, emotional disturbances, poorly-sustained parenting-and-addiction, lack of good sexual education, lack of self-regulation motivational skills, religious environments and environmental stimuli, incitement and the core of abnormal sexual socialization.