Inconsistency in parenting is a factor that may influence children’s mental health. A questionnaire, measuring three parental inconsistencies (temporal, situational, and father-mother inconsistency) was administered to adolescents in nine countries to assess its association with adolescents’ psychological disorders. The results show that parental inconsistency varies across cultures. Temporal inconsistency is not correlated with the other two inconsistencies. Temporal and father–mother inconsistencies, but not the situational inconsistency, were associated with adolescents’ psychological disorders. The associations between parental inconsistency and psychological disorders differed across cultures.