<p>Parents of children with neurodevelopmental disorders (NDD) have been found to experience higher levels of parenting stress compared to parents of typically developing children as well as parents of children with other forms of psychopathology. We aimed to examine parenting stress in parents with children with attention-deficit/hyperactivity disorder (ADHD) and/or autism spectrum disorder (ASD), and the possible associations between parenting stress, child psychosocial functioning and the parent’s own symptoms of NDD. Participants consisted of 86 mothers and 37 fathers of children 8–18 years old (n = 97) diagnosed with ADHD and/or ASD. Parents were interviewed with the Swedish Parental Stress Questionnaire (SPSQ) and completed self-rating scales: Autism Symptom Self-ReporT for Adolescents and Adults (ASSERT) and the ADHD-Rating Scale (ADHD-RS). The Children’s Global Assessment Scale (C-GAS) was used as a clinical-rated measure of child psychosocial functioning. Results showed that both mothers and fathers experienced high levels of parenting stress, although mothers, when compared with the child’s father, reported higher levels in the domains of role restriction, health problems and total scale. No differences in parenting stress were found relating to their child’s diagnosis. Both parental NDD symptoms and child psychosocial functioning were found to be associated with levels of parenting stress in mothers, and the association remained in the adjusted model accounting for family context factors and child factors. Parental stress should be considered when planning interventions for families with children with ADHD or ASD.</p>