Although studies have examined the association between individuals' mindfulness and romantic relationship quality, additional empirical research is necessary to specifically comprehend the potential factors influencing the association between mindfulness and couple quality. The purpose of the present study was to investigate the association between mindfulness and couple quality and the mediating roles of self‐care and engagement in shared relationship activities among 1,331 participants in a southeastern region of the United States. The authors of this study conducted a multiple mediation analysis using longitudinal data to investigate the mediating effects of caring for self and engagement in shared relationship activities. The research findings in this study indicated that an individual's mindfulness had a significant direct association with couple quality in a romantic relationship. In addition, participants' couple quality was significantly mediated by self‐care and engagement in shared relationship activities with a romantic partner. Implications for educators, researchers and practitioners are discussed.