This study was carried out to examine the social determinants of the professional identity of secondary school teachers in Khoy city. In this survey research, the statistical population included all secondary school teachers in Khoy, totaling 760 individuals according to the Education Department's statistics. Based on Morgan's table, the sample size was determined to be 255. Five standard questionnaires were used to measure the main variables of the study, and the collected data were analyzed using SPSS software. The results showed that the level of professional identity among teachers, as well as the average dimensions of professional identity (teaching and learning, student development, school development, professional relations and services, and personal growth and development), were high. The average values of the independent variables indicated that the level of religiosity was high, alienation was low to moderate, social capital was moderate, and happiness was moderately high. The results of the independent variables showed that the levels of religiosity and happiness among secondary school teachers in Khoy city were high, and they had a low level of work alienation. Bivariate analysis results indicated a significant relationship between the independent variables (work alienation, religiosity, happiness) and professional identity and its dimensions. The results of the multiple regression analysis, with an adjusted coefficient of determination of 51.6%, showed that the independent variables explained 51.6% of the variance in professional identity. Additionally, based on the standardized beta coefficient, the variable of happiness had the highest contribution (β = 0.317), while religiosity had the lowest contribution (β = 0.118) in explaining the professional identity of teachers.