A grasp of various social factors which influence adolescents’ identity can prevent identity crisis. Hence, the present study was undertaken to investigate the impact of peers, mass media, and school performance on adolescents’ identity. In this survey the population of the study included the entire high school students in Tehran (94000 students). The sample size was determined to be 382 based on Cochran’s formula and random multi-stage cluster sampling method was used. The instrumentation comprised a researcher-made questionnaire with desirable validity and reliability.Correlation coefficient and regression analysis were used for the purpose of testing the hypotheses. Correlation results indicated that there was a significant relationship between social factors (peers, mass media, and school) and adolescents’ identity (sig.=0.000). The highest association was observed between peers and identity (r=0.501). School came next (r=0.412) and mass media showed the weakest correlation (r=0.332). Moreover, results of regression analysis showed that the aforementioned social factors could explain the variance in adolescents’ identity. More specifically, a one standard deviation increase in school performance, peers and mass media, in turn, leads to a 0.211, 0.321, and 0.2 standard deviation increase in adolescents’ identity.