The ability to delay gratification is related to success in school and other aspects of life. Genetic as well as environmental factors such as parenting style partly explain the development of delay of gratification (DoG). However, it is unclear whether parental personality impacts children’s DoG, and how maternal and paternal personalities contribute to this relationship. The present study investigates the relationship between parental personality and 45-month-old children’s DoG (N = 329). Personality was measured using the NEO-Five-Factor-Inventory-30, DoG was operationalized through waiting time in the marshmallow test. In model 1, using only maternal data to predict DoG, maternal openness to experience was associated with shorter waiting time of the child in the marshmallow test, whereas maternal agreeableness was associated with longer waiting time. In model 2, using only paternal data to predict DoG, paternal agreeableness was related to longer waiting time. In model 3, combining maternal and paternal data to predict DoG, maternal openness to experience as well as paternal agreeableness remained significant predictors of DoG. The present study underlines the influence of both parents’ personalities on the development of children’s DoG and indicates differential maternal and paternal effects. Future studies should investigate the relationship between parental personality and children’s DoG in detail and take further factors into account, such as genetic factors, other environmental factors and the personality of the child.