This study assessed the links between maternal sleep and mothers' perceptions of their attachment relationship with their infant among women at risk for postpartum depression by virtue of having been depressed during pregnancy. Sixty-two mothers completed sleep diaries and questionnaires at 3 and 6 months postpartum. Regression analyses, controlling for depression severity and infant temperament, revealed significant prospective correlation between maternal shorter total sleep time at 3 months and lower scores on a mother-infant attachment questionnaire at 6 months. At 6 months, the longer time mothers were awake tending to their infants the lower were their attachment scores. The findings suggest that improving sleep of mothers who suffered from prenatal depression may have a positive effect on mothers' self-reported relationship with their infants.