In line with the increased interest in studying implicit language attitudes, this study aims to explore implicit attitudes towards Catalan and Spanish in the multicultural and multilingual context of Catalonia (Spain) using the Implicit Association Test (IAT). A sample of 113 adolescents completed the IAT and a set of explicit measures of attitudinal and motivational variables. Results show a general preference for Catalan over Spanish. However, differences appear when home language is taken into consideration, as participants tend to prefer their home language. The paper discusses the relationship between implicit and explicit attitudes, highlighting the importance of incorporating implicit measures in language attitudes research in Catalonia.