Minimal data set.

Professional identity has become a central topic in teacher education research and a crucial factor in shaping teachers’ self-perception and perspectives on various aspects of their profession, including teacher roles, scholarly research, curriculum design, classroom instruction, instructional methods, and strategies, as well as their interactions within the educational context. Despite the considerable scholarly interest in teacher identity development, relatively few studies have considered how to measure teacher professional identity. This study developed and validated a new measurement of professional identity among Chinese pre-service teachers from an English language education program. A total of 560 pre-service teachers majoring in English language education were invited to participate in a survey and 542 questionnaires were deemed valid and subjected to analysis. Through this analysis, a scale with 17 items was developed, focusing on three different dimensions: professional self-efficacy, career commitment, and professional knowledge. After excluding items with a relatively poor correlation with factor loading, the final scale consisted of 13 items. The results showed that the developed scale has relatively good reliability (α = 0.939) and structural validity (χ2/df = 2.46, p < .001, CFI = 0.978, TLI = 0.971, SRMR = 0.033, RMSEA (90% CI) = 0.071 0.054, 0.089). This study may provide a quantitative instrument for future research to measure professional identity among pre-service teachers, both in Chinese and other contexts.