Maternal knowledge of child development has been shown to affect how mothers raise their children and the environments they provide. This study examines maternal knowledge of child development and whether level of knowledge varies by content area. Additionally, this study explored maternal characteristics that predict knowledge levels globally and by content area. Low-income women (N = 203) in the waiting room of an obstetric clinic (n = 97) and pediatric clinic (n = 106) in a southern state were asked to complete questionnaires on typical child development and demographic characteristics. Overall, women correctly answered 65% of the criterion-referenced knowledge questions. Mothers lacked the most knowledge about infant sleep patterns and developmental ability of 6-month-old infants. Maternal education, race, number of children, and assistance with childcare were significantly related to maternal knowledge. Identifying gaps in maternal knowledge and characteristics that correspond to knowledge deficits provides insight into how best to tailor educational interventions for mothers. ©2005 Michigan Association for Infant Mental Health.