The aim of this research was to compare parental stress, coping strategies and social support perceived in families of children with low functioning autism (n = 8), high functioning autism (n = 10), Down syndrome (n = 12) and parents of typically developing children (n = 20). Specifically, the objective was to investigate which variables (coping strategies and perception of social support available) might better predict different stress outcomes in the four groups. Parents were asked to fill in three questionnaires: Parent Stress Index, Coping Orientation to Problems Experienced, and Social Support Questionnaire. Significant differences among groups in all of the variables considered were found. These results suggest the advisability of fostering functional coping strategies and social support received in families of children with disabilities, and especially in those with children with low functioning autism.