The present study employed a family systems approach to investigate the effects of level of autism severity on family functioning as mediated by parental coping. Participants were mothers of children with autism who were volunteers in an ongoing research program conducted within a university-based treatment center (N=146). Gilliam Autism Rating Scale, Second Edition (GARS-2) scores were available for all of the children and, as part of the broader program, parents completed the Coping Scale for Adults, which assesses a range of coping styles, and the Family Environment Scale, which provides positive and negative indicators of family functioning. Data analyses indicated that nonproductive coping significantly mediated the relationship between level of autism severity and family cohesion and conflict. Results also suggested that level of autism severity was negatively related to family conflict. The study further examined the use of specific coping styles on family cohesion and conflict. Evaluation of findings suggest that parents who have a child diagnosed with severe autism may be employing maladaptive coping strategies, such as wishful thinking, blaming one's self, or avoiding the situation. Implications for intervention approaches for individuals working with families of children with autism are suggested.