Background: Children's emotional responses and physiological reactivity to conflict were examined as mediators and moderators in the associations between exposure to parental marital conflict and child adjustment and cognitive problems. Method: One hundred and eighty elementary school children participated. In response to a simulated argument, children's skin conductance level reactivity (SCLR) was examined, and their emotional responses (reported and observed anger, sadness, and fear) were assessed. Results: A higher level of SCLR was a robust risk factor for various child outcomes, mediated boys' internalizing difficulties in the marital conflict-child functioning link, and functioned as a vulnerability factor for girls' externalizing, internalizing, and cognitive problems. Increased anger (for boys) and sadness (for girls) exacerbated adjustment difficulties related to marital conflict. Conclusions: Findings illustrate the aggregation of risk in relation to child and family characteristics.