In March 2020, the disease caused by SARS-CoV-2 coronavirus has been declared a “pandemic” by the World Health Organization. To reduce the risk of contamination, many countries have ordered a strict lockdown characterized by social distancing and restrictive isolation measures. This pandemic has profoundly affected couples’ daily lives. The objective of our three-wave longitudinal study (N = 229) was to examine the trajectory of couple satisfaction during 1 year of COVID-19 pandemic and lockdown, with dyadic coping as a predictor of the intraindividual change. Our results showed that couple satisfaction remained stable over time. Dyadic coping was also found to be a predictor of intraindividual changes in partners’ Relationship Dissatisfaction and Difficulties in Problem-solving Communication during the pandemic: Relationship Dissatisfaction increased over time when dyadic coping was weak, while Difficulties in Problem-solving Communication decreased over time when dyadic coping was high. The discussion underlined the importance of focusing couple interventions on dyadic coping during stressful situations, like the COVID-19 pandemic. (PsycInfo Database Record (c) 2022 APA, all rights reserved)