With the comprehensive expansion and increased attention to social work, the overall level of professional identity among young social workers is higher than that in previous studies. Regarding influencing factors, individual characteristics such as gender, age, education level, and marital status, as well as professional characteristics such as years of social work experience and the scale of the social work agency, all have varying degrees of impact on the professional identity of young social workers. Mechanistically, both individual and environmental factors contribute to the professional identity of young social workers. Path analysis indicates that individual-organization fit has a higher utility for the professional identity of young social workers compared with public service motivation. Therefore, to enhance the professional identity of young social workers and thereby improve the professionalization level of the social work workforce, it is necessary to focus on guiding young social workers to dedicate themselves to the “original aspiration” of serving the public, while also emphasizing the creation and optimization of work environments, providing professional support resources for young social workers, improving individual-organization fit, and achieving a “win-win” situation for the personal development of young social workers and institutional development.