Recent research has revealed the significant role of perceived cultural differences, or cultural novelty, in shaping the intercultural experiences of diverse individuals. Yet, our understanding of how cultural novelty influences the relationship between language and cultural adjustment remains limited. This study addresses this gap by examining the moderating effect of cultural novelty on the relationship between foreign-language proficiency and cultural adjustment. Survey data from 1,092 international students in five countries were analyzed using mediation and moderated mediation analyses. The moderating effect of cultural novelty was confirmed, specifically in the host-language context, where higher cultural novelty significantly weakened the relationship between host-language proficiency and socializing with domestic students. Moreover, this research illuminates the influence of the lingocultural context on cultural adjustment. This study has important implications for higher education institutions. It demonstrates how cultural novelty can impact the ability of foreign-language proficiency to enhance student adjustment and the overall educational experience.