Previous studies on parental behavior have primarily focused on maternal behavior, with little research directed at observing paternal behavior. The effects of neonatal paternal deprivation and early deprivation on adult parental behavior and estrogen receptor α (ERα) especially remain unclear. This study examined whether paternal deprivation or early deprivation has long-term effects on the parental behavior and central ERα expression of adult mandarin vole offspring. The parental behaviors of adult mandarin voles that suffered paternal deprivation or early deprivation were observed with their own pups at 0, 13 and 21 days of age. Central ERα expression was also examined in adult virgin voles with different neonatal treatments using immunocytochemistry. The results indicated that (1) levels of parental care and sociability in adult offspring were reduced due to paternal deprivation and early deprivation; (2) ERα expression in the stria terminalis (BNST), medial preoptic area (MPOA), ventromedial hypothalamic nucleus (VMH) and arcuate hypothalamic nucleus (Arc) were also reduced by paternal deprivation and early deprivation; (3) ERα expression in the BNST, MPOA, and VMH of control females was higher than that of control males, but ERα expression in the Arc was lower. Our findings show that paternal care plays an important role in the development of parental behavior in offspring. Also, because paternal deprivation and early deprivation impaired sexual differences, the alteration of parental behavior may be associated with decreased ERα expression.