Moderating effects of family factors on the association between children’s reinforcement sensitivity and problem behaviour have been examined in a community sample of 533 children aged from 3 to 17 years. Family type and living in urban areas exacerbated the effect of sensitivity to reward on externalizing, internalizing and impact of problems on everyday life; a high level of the father’s education exacerbated the effect of sensitivity to reward on externalizing; family aggression and harsh parenting were found to strengthen the link between sensitivity to reward and the impact of problems on everyday life, whereas family cohesion buffered the negative effect of sensitivity to reward on externalizing and the impact of problems in everyday life.