We contribute to the literature on the determinants of socioeconomic health disparities by studying how the health behavior of adolescents may arise from the degree of communication between parent and child. Parent-child communication may function as a mediator between family background and subsequent poor health behavior, potentially reconciling previous mixed e vidence on the rela tionship between child health and social status. Using data from a unique German child health survey we construct an index of parent-child communication quality by comparing responses to statements about the childrens wel l-being from both children and their parents. Applying the constructed communication measure in a continuous treatment empirical framework, allowing for estimation of non-linear eff ects, our resul ts show that improved parent-child communication monotono usly reduces the smoking prevalence of adolescents by as much as 70%, irrespective of social background. More complex relationships are found for risky alcohol consumption and abnormal body weight.