Research on ADHD in children and adolescents has traditionally focused most on the genetic and neurobiological aspects of the disorder, but the role of family relationships has been much less systematically examined. There is growing evidence that the quality of interparental relationships and children’s ADHD symptoms are reciprocally related. Because former findings appear to be inconsistent, this meta-analysis aims at summarizing previous research in order to assess whether there are robust differences in the quality of interparental relationships between parents of children with ADHD and parents of healthy children. This meta-analysis of 15 studies with 43 effect sizes revealed a small, but significant difference (d = .24) and indicated that parents of a child with ADHD report poorer relationship quality than parents of healthy children. This effect was moderated by the child’s age and did not depend on whether the child had a comorbid Oppositional Defiant Disorder or Conduct Disorder.