Quality physical education programs are essential in preventing childhood obesity, and its implementation depends on the quality of preservice physical education teachers (PPETs) who may develop a strong teacher identity in physical education. However, existing research in PPET-TI is very sparse. This study aimed to examine the essential elements of PPET-TI and the psychometric properties of the scale measuring PPET-TI. Two studies were conducted using a mixed-methods research design. In study 1, semi-structured interviews were conducted with 19 PPETs. Three essential themes were identified: self-definition of roles and projected professional positions, teaching goals, and professional responsibilities for self-growth and changing the physical education profession. In study 2, survey items were developed based on results from study 1 and a literature review, which were evaluated by 10 experts to establish content validity. A survey of 26 items was distributed to 552 PPETs’ to examine validity and reliability. Confirmatory factor analysis and model specification revealed an adequate model fit to the data for a 17-item PPET-TI Scale consisting of three domains: self-definition, teaching goals, and professional responsibilities. Convergent validity, criterion validity, and discriminant validity of the scale scores were also adequate. The scores of the PPET-TI Scale showed an acceptable internal consistency (Cronbach’s alpha = .91 for the entire scale). It is recommended to use the PPET-TI Scale for PPET recruitment, PETE program effectiveness evaluation, and PETE curriculum improvement. Future studies may use the PPET-TI Scale to identify influencing factors of identity development.Curriculum and Instructio
