Previous studies involving pre-school and school-aged children found that marital conflict negatively impacts children's socio-emotional development both directly and indirectly though parenting. Additionally, studies have found that parenting predicts numerous infant and child outcomes such as affect. Although research supports that marital functioning affects parent-child relationships during early childhood through adolescence, studies assessing how marital functioning and parenting influence socio-emotional development during infancy is scant. This longitudinal study examined associations between marital functioning, parenting, and infant affect over time for infant-mother and infant-father dyads during the Still-Face Paradigm (Tronick, Als, Adamson, Wise, & Brazelton, 1978). Structural equation modeling results indicated that for fathers, marital functioning related both directly and indirectly to changes in infant affect during the Still-Face; parenting also mediated relations between marital quality and infant affect. For mothers, sensitive parenting predicted changes in affect but marital functioning did not play a role in the dynamic in infant-mother dyads.