We aimed to identify maternal characteristics predicting interpretation of infant emotions, as well as relations between such interpretations and mother-infant stress. Specifically, we investigated (1) prospective associations between maternal dispositional mindfulness and interpretation of infant emotions, and (2) concurrent associations between maternal interpretation of infant emotions and mothers’ and infants’ cortisol during a dyadic stressor in a non-clinical community sample (n = 78) of mother-infant dyads. Mothers completed the Five Facet Mindfulness Questionnaire at 3 months postnatal, and the IFEEL Picture (...) infant emotion interpretation task at 6 months postnatal. At 6-months, mother-infant dyads completed the Face-to-Face Still Face paradigm, and physiological stress was assessed via salivary cortisol. Regression analyses revealed significant links between aspects of maternal mindfulness – specifically, Observing, Describing, and Acting with Awareness facets – and infant emotion interpretation; more mindful mothers’ emotion ratings were less negatively biased and covered the full spectrum of infant emotions, congruent with the range of responses given by a low-risk reference sample. In turn, less negativity bias and greater interpretive congruence predicted lower infant and mother cortisol during the stress session, with effects small-medium in size. Findings highlight the potential role of maternal interpretation of infant emotions in mindful parenting. (shrink)