Identity formation in immigrants is the central focus of research that relates to religion and immigration. Immigrants in the Unites States generally have held on to religion as a source of constructing religious identity or preserving an ethnic identity or combining both. For instance, in the United States, the mosque plays a central role in the lives of the Muslim immigrant community as a powerful religious and cultural symbol. This function of the mosque enables scholars to clarify Muslims' identity in the Western World. This paper examines how the mosque affects the identity formation of Somali adolescents in Columbus, Ohio, the second largest settlement of migration for Somali Muslim refugees after the civil war in Somalia in 1990s. Somalis have considerable difficulties during the first stage of resettlement in the Diaspora and thus, have established several local religious institutions (mosque or masjid) as well as community associations. In this study, I focus on the largest and most organized mosque as a sample. I have spent 5 months as a participant observant in the setting and conducted 15 in-depth interviews with male and female adolescents, age ranging from 13 to 19. As a result, this paper states three distinct movements among adolescents who attend the mosque's religious, educational, and social activities. The first two movements are identity transformations from national and ethnic identity to religious identity; one movement relating to moving away from the wider American society and culture and the other one relating to integrating developed religious identity with American society and culture. The last movement, however, has experienced identity conflict between ethnicity, religion, and the American society. In conclusion, this paper argues that the mosque not only plays a stabilizing role in the construction of religious identity which diverges in opposite directions among Somali adolescents, but also creates identity conflict for a considerable amount of Somali adolescents.