Existing research shows inconsistent findings on the relationship between marital satisfaction and cognitive functions in later life . Focusing on different domains of cognition and a longitudinal perspective, this study aims to examine long-term changes of cognitive functions in older adulthood and the role of marital satisfaction in these changes. Latent curve modeling (LCM) was applied to six-year longitudinal data from 751 older adults (Age = 67.62 ± 5.31), assessed every two years. Cognitive functions was assessed across five distinct domains: word fluency, verbal ability, backward digit span, numerical comparison speed, and associative learning. Results revealed that:(1) marital satisfaction, backward digit span, and verbal ability declined significantly over time, while associative learning showed a significant increasing trend. (2) The marital satisfaction has a long-term process effect on cognitive functions. Specifically, the long-term process of marital satisfaction was negatively associated with the long-term process of word fluency and verbal ability. In addition, the initial level of marital satisfaction was positively associated with the the long-term process of word fluency, but negatively associated with that of backward digit span. This study revealed the developmental trajectories of marital satisfaction and cognitive functions and their changing associations over time. The findings provide a new perspective on existing debates by examining different domain of cognition longitudinally and highlight how distinguishing unique domains of cognitive functions allows for a more comprehensive understanding of the relationship between marital satisfaction and cognitive functions.