Past research suggests that adoptees face a higher risk of insecure attachment and encounter more challenges related to trust and commitment in their romantic relationships compared to nonadopted individuals. However, limited studies have used nationally representative data to systematically examine these relationships, and even fewer, if any, have explored potential gender differences in this context. Using data from a representative sample of newly married couples in the United States (n = 2,110), we examined the relationship between adoption status and multiple measures of marital security, including gender as a potential moderator. Findings from OLS regression models indicate that adult adoptees exhibited similar levels of both avoidant and anxious attachment, trust, and commitment when compared to nonadoptees. Gender differences in attachment patterns were observed among nonadopted individuals, with nonadopted women showing significantly lower levels of avoidant attachment and significantly higher levels of anxious attachment compared to nonadopted men. Interestingly, however, these gender differences were not significant among adoptees, suggesting that adoption status potentially attenuates gender-related differences in attachment. Our findings support the view that adoptees demonstrate resilience and, overall, experience comparable relationship outcomes to nonadoptees in adulthood.