Problematic of this study is focused on how male teenagers of Mashhad make meaning of and represent relationship with opposite sex? This research uses constructive interpretation approach, grounded theory method and deep interview technique. Purposive theoretical sampling was used to select 20 participants for interviews. Consequently, data were coded in 13 axial categories and one core category. Research findings indicate that teenagers turn to opposite sex because of emotional problems, intense sexual desire and to seek membership in peer groups. Relationship with opposite sex is a way by which they respond to their sexual need and need to social identity and it helps them to gain social acceptance among peers and reach dominance and prestige through having multiple relationships. Based on current study, experience of relationship with opposite sex results in dependence, emotional pleasure, sexual pleasure, mental engagement and educational problems in teenagers’ lives.