Objective To investigate the impacting factors on the professional identity of railway young workers and the relationship of the professional identity and subjective well-being.Methods The sample consisting of 5 762 young workers was selected from railway enterprises by stratified and random sampling according to the proportion.Occupational professional identity Scale and Index of Well-being,Index of General Affect Scale were used.The affect of the variable,such as sex,age,working years,educational background and income on professional identity were studied.Moreover,the relationship between professional identity and subjective well-being was reported.Results (1) Professional identity ascended witb the increase of ages,and there was significance between three groups(F=6.667,P＜0.05).(2)Professional identity ascended with the increase of length of service (F=5.147,P＜0.01),but it dropped at the point of 9-12 years.(3) The professional identity of workers with bachelor degree was higher than that with junior college education background.and there was significance between three groups (F=3.538,P＜0.05).(4)The workers who had more than 3 500 RMB monthly salary was regarded on the top in professional identity,while those whose monthly salary were under 2 500 RMB was in the lowest level (F=42.275,P＜0.01).(5)The result of linear regression indicated that the degree of professional identity can forecast the degree of subjective well-being(R =0.534,P＜0.01).Conclusion The professional identity of railway young works was affected by their ages,the length of service,the educational degree and salary,The professional identity can forecast subjective well-being.