This study aimed to develop and psychometrically evaluate a self-report instrument to assess attitudes and self-efficacy of Physical Education (PE) preservice teachers toward teaching linguistically and culturally diverse PE classes. An 18-item instrument was developed for the initial tests. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were conducted on two independent samples of PE preservice teachers (n[subscript efa] = 254; n[subscript cfa] = 183). The EFA revealed a four-factor structure: attitudes toward multilingualism, attitudes toward linguistic simplification, language awareness in lesson planning, and self-efficacy to teach culturally diverse classes. The reliability scores for the four factors range from 0.61 to 0.76. CFA showed that the constructs demonstrated a good fit to the model (S-B B?2(48, 183) = 70.40, p = 0.02, robust RMSEA = 0.05, robust CFI = 0.94), confirming the construct validity with high-dimensional factor loadings (ranging from 0.54 to 0.94). Discriminant validity was revealed through correlational analysis.