Background: Increased parental stress is strongly related to the severity of autism spectrum disorder (ASD) symptomatology. Parents' coping strategies and social support issues add to the complexity of this relationship. Aim: The present study investigated the relationship between self-regulation skills and parenting stress in parents of nonverbal children with ASD. Methods and procedure: The Parenting Stress Index--Short Form (PSI-SF) was administered to 75 families, and self-regulation scores on a Motor Behavior Checklist for children (MBC) were recorded by students' class teachers (level of functioning-behavioral problems). In addition, interviews were conducted with a focus group of six parents (four mothers and two fathers) to explore the underline factors of parental stress in-depth. Results: Correlation analyses revealed that parenting stress was positively correlated with elevated scores on MBC children's self-regulation subscale. On the other hand, parenting stress was negatively correlated with the level of social functional support reported. Qualitative data were analyzed using transcripts, revealing additional stressors for families and parents, and resulting in recommendations to overcome these factors. Conclusions and implications: Aiming at developing strategies to improve self-regulation skills in nonverbal children with ASD may be particularly important in reducing parental stress for families having nonverbal children with autism and other developmental disabilities. Parents' stressors and suggestions during interviews are also discussed.