Although child corporal punishment can lead to adverse health outcomes in children, this practice remains prevalent in Japan. This study investigates whether, under Asian family norms, fathers' job stress is a risk factor for mothers' frequent use of child corporal punishment. A study sample of 522 children ages 0 to 6 years was obtained from a population-based survey in Tokyo. Data from mothers' self-reports of maternal caretaker child corporal punishment were regressed on paternal job stress using logistic regression analysis. Covariates include child age (months), child gender, number of children in the household, maternal education, maternal adverse childhood experiences, and annual household income. Maternal psychological distress was hierarchically included in the model. Paternal job stress was significantly associated with maternal frequent use of child corporal punishment independent of maternal psychological distress and other known risk factors such as child's age, maternal education, and maternal adverse childhood experiences. The results indicate that job stress may be a risk factor for parental child corporal punishment. Employers can contribute to improving children's health and safety in the household by designing workforce policies to reduce employee's stress and by offering psychoeducational programs for parents.