- Research on immigration underscores the importance of language acculturation in successful adjustment to life in a new country. However, the profound impact of different levels of language proficiency between immigrant spouses on their married life is an understudied topic. The current study explores whether differences between immigrant spouses in host language proficiency predict marital satisfaction in their first four years in the host country. Using a three-wave longitudinal study, with intervals of one to two years, we collected data from 316 married couples who immigrated from the Former Soviet Union to Germany and Israel. Language proficiency and marital satisfaction were measured via self-report questionnaires. We conducted an Actor-Partner Interdependence Model analysis to control for dyadic and time data dependencies. The results indicate that differences between spouses in their host language proficiency predict marital dissatisfaction, and that this effect is exacerbated over time. These associations held across gender and host country. The findings are discussed in light of the gap-distress model.