Purpose: The purpose of this paper is to examine the impact of classroom interdisciplinary diversity, a type of classroom diversity that has been under-examined by previous literature, on the formation of university students' entrepreneurial intentions (EI). Design/methodology/approach: Based on Ajzen's theory of planned behaviour and the interactionist model of creative behaviour by Woodman "et al." (1993), this paper provides empirical evidence demonstrating that classroom interdisciplinary diversity is important in the formation of university students' EI at early educational stages using a cross-sectional study design and survey data on first-year business school students and partial least squares analysis. Findings: Classroom interdisciplinary diversity is important in the formation of university students' EI through its positive impact on entrepreneurial perceived behavioural control (PBC) (self-efficacy), a key antecedent of EI. Practical implications: The results have important implications for educational practice as well as for both public and private organisations willing to promote entrepreneurial activity, in particular, the positive effects of combining people with different profiles and career fields of interest on entrepreneurial PBC (self-efficacy). Originality/value: This study contributes to the scant literature on early university experiences in entrepreneurship education and their influence on EI. It studies the impact of an under-examined dimension of diversity (classroom interdisciplinary diversity) on the formation of students' EI.