Background Maternal social support has a critical impact on breastfeeding outcomes. Fathers, in particular, are known to be especially influential. We aimed to explore paternal knowledge and attitude toward breastfeeding, and possible association with breastfeeding rates at discharge, in a cohort of fathers from an Italian tertiary referral center for neonatal care.Methods In this cross-sectional study, we enrolled fathers of healthy term neonates born at our hospital from March to May 2019. At discharge, a self-administered structured questionnaire was proposed to fathers. Fathers were required to rate their degree of agreement to 12 items on a 5-point Likert scale. A total score was obtained from their answers. A higher score was indicative of a greater knowledge/positive attitude toward breastfeeding. Subjects’ basic characteristics and mode of feeding at discharge were collected.Results Fathers showed a generally solid knowledge of maternal (87%) and neonatal (98%) benefits of breastfeeding, skin-to-skin (99.5%), rooming-in (79%), and responsive feeding (67.5%); conversely, only 51% knew about the recommended use of pacifiers. Fathers felt personally involved in their babies' feeding in 79% of cases, regardless of the type of feeding. A positive association was found between total score and exclusive breastfeeding rates at discharge (p = 0.04, OR 1.07; 95% C.I 1.002-1.152). Conclusions This study underlines the importance of including fathers in the promotion of breastfeeding, expanding the classic mother-baby dyad to a more modern mother-father-baby triad. This aspect may ultimately impact breastfeeding outcomes, although further studies are needed to confirm our results.