Introduction: Identity is formed through our understanding ofourselves and what others perceive of our actions and how we dothings. Formation of professional identity includes development,advancement and socialization through social learning of specificknowledge and skills obtained within the context of professionalroles, new attitudes and values.Methods: This qualitative study used content analysis approachto explain the professionalization process of 22 social workersworking in 14 public hospitals in Tehran based on theirexperiences. The data were collected through semi-structuredinterviews, observation and writing in the field.Results: Eleven categories and three themes of entry into theprofession, identity formation, and identity ownership wereextracted out of data analysis. Revealing the process, barriers andfacilitators of professionalization of hospital social workers wasthe results of this study.Conclusion: Certain individual characteristics were factorsfor the tendency of participants to choose this profession. Theparticipants’ understanding of their profession was formed, whenstudying in the university through learning relevant knowledge,skills, views and professional expectations. Achieving a singleidentity and professional pride and self-esteem are achievementsof identity ownership.Keywords: Content analysis, Hospital, Social worker, Professionalism