Research described risk factors for maternal use of harsh discipline, but knowledge about determinants of paternal harsh discipline is lacking. This study aimed to identify determinants of harsh discipline and whether this differed between mothers and fathers. Harsh disciplining practices were self-reported by Dutch parents of 3-year-old children. Data were available for 3,756 children and both parents. Younger parental age, non-Western national origin, family dysfunction, psychopathology, and delinquency history were independently associated with an increased risk of maternal and paternal harsh discipline. Indicators of socioeconomic status (e.g., financial difficulties and educational level) were also associated with harsh discipline, but in mothers only. Our results suggest that preventive interventions should ideally be applied early in children's lives or even before birth, given the prevalence of parental harsh discipline in young children. These interventions should have a special focus on socially disadvantaged families and on parents with psychopathology and family stress.