Social participation represent one of the major outcomes of inclusive education. Students with additional support needs often encountered negative attitudes of social acceptance exhibited by their typically developing peers hindering their social participation in the educational context. This study explored the multicomponent structure of Portuguese children's attitudes toward their peers with disabilities using a modified short form of the Chedoke-McMaster Attitudes toward Children with Handicaps scale (CATCH). In particular, this study aimed to: (1) determine the factor structure of the CATCH; and (2) evaluate the measurement invariance across age and gender. To identify the CATCH factor structure, exploratory and confirmatory factor analyses were conducted on data collected from 1,038 children aged 8-18 years. Analyses revealed that a modified short form of the CATCH consisting of a 20- item measure with a three-factor structure displayed acceptable fit and internal consistency indices. This model proved to be invariant across groups. The Portuguese-modified short form of the CATCH, in which cognitive, affective, and behavioral dimensions are represented, has acceptable psychometric properties and the potential to evaluate the effectiveness of educational programs designed to improve children's attitudes.