Fathers play a critical role in parenting and in shaping child outcomes. However, the neurobiological underpinnings of successful adjustment to fatherhood have not been well-specified. Empathy and mentalizing abilities may characterize more effective fathering. These abilities may be supported by the functional connectivity (FC) of brain regions associated with social cognition and executive control. We used a seed-region-based approach to assess resting-state FC (rsFC) of the medial prefrontal cortex (mPFC) in 40 expectant fathers. We tested associations between mPFC whole-brain rsFC and fathers' self-report measures of empathy during pregnancy, as well as their ratings of father-infant bonding and fathering behaviors at six months postpartum. Stronger prenatal rsFC between the mPFC and precuneus, frontal pole, planum polare, and orbitofrontal cortex (OFC) was negatively associated with self-reported empathic concern and perspective-taking, whereas mPFC rsFC with the lateral occipital cortex (LOC) was positively associated with self-reported perspective-taking. Additionally, stronger prenatal connectivity between the mPFC rsFC and the superior parietal lobule and LOC regions predicted father reports of postpartum bonding with infants, and stronger prenatal mPFC rsFC with the LOC predicted more effective postpartum parenting. This study is the first to measure rsFC in expectant fathers as a predictor of subsequent adjustment to fathering.