We are the first to estimate the causal effect of parental education on a wide range of the adult offspring's mental health outcomes. Theoretical considerations predict positive direct and indirect effects of parental education on the offspring's mental health. But the relation between parental education and mental health outcomes is plagued by endogeneity. To circumvent this problem, we exploit exogenous variation in schooling which is completely unrelated to the offspring's mental health. In contrast to our theoretical considerations, we find no positive effects of parental education on the offspring's mental health. Moreover, preliminary results point at a negative effect of parental education and the offspring's mental health.