Cognitive health is often explored within social relationships, where spousal relationships and the bond between the partners have been widely documented in previous literature. However, there has not been enough literature that explores whether age-heterogeneous marriages influence individuals' cognitive health differently for both men and women. Comparing age heterogeneous marriages with age homogeneous marriages, this study explores if men and women have different cognitive health outcomes. Data has been used from the National Social Life, Health, and Aging Project (NSHAP), a longitudinal, population-based study of older adults in the United States, conducted in 2010-2011 (wave 2). The results from the interaction models show a gendered pattern. For older men in age heterogenous marriages, a significant negative association between spousal age gap and cognitive functioning was found as they aged compared to men from age homogenous marriages. However, for younger women in age-heterogeneous marriages, the association is steady across their age compared to women in same age marriages. These findings highlight the importance of exploring the influence of spousal age gap on cognitive health for future longitudinal studies in order to further our understanding of marriage, age gap, gender, and cognitive health.