This study examines the effects of social tie strength, value fit and affect-based trust of overseas workers on their cultural knowledge acquisition in foreign countries. Based on the assumption that cultural knowledge is acquired through social interactions, the research model encompassed 3 social-related independent variables and tested empirically from 536 interpersonal relationships reported by 136 respondents. The results revealed that social tie strength and value fit have positive impacts on cultural knowledge acquisition not only directly but also indirectly, through the mediation role of affect-based trust. However, the mediation effect differs between relationships with local nationals and relationships with non-local nationals. Specifically, affect-based t rust is essential for the effect of social tie strength to local nationals instead of that to non-local nationals; moreover, the mediation effect is sufficient on value fitted non-local nationals but is incomplete on value fitted local nationals. The implications of the findings and the need for future research were also discussed.