Postnatal mother-infant bonding refers to the early emotional bond between mothers and infants. Although some factors, such as maternal mental health, especially postnatal depression, have been considered in relation to mother-infant bonding, few studies have investigated the role of infant temperament traits in early bonding. In this study, the effects of maternal postnatal depressive and anxiety symptoms and infant temperament traits on mother-infant bonding were examined using both mother and father reports of infant temperament. Data for this study came from the first phase of the FinnBrain Birth Cohort Study (n=102, father reports n=62). After controlling for maternal symptoms of depression and anxiety, mother-reported infant positive emotionality, measured by infant smiling was related to better mother-infant bonding. In contrast, infant negative emotionality, measured by infant distress to limitations was related to lower quality of bonding. In regards to father-report infant temperament, only infant distress to limitations (i.e., frustration/anger) was associated with lower quality of mother-infant bonding. These findings underline the importance of infant temperament as one factor contributing to early parent-infant relationships, and counseling parents in understanding and caring for infants with different temperament traits.