Studies have shown that parents of children with autism spectrum disorders experience stress in parenting their children (e.g. Anyanwu et al. in Glob J Health Sci 11(8):51–60, 2019; Ayers in Self-care: why parents of children with disabilities must nurture themselves, 2012. http://www.disaboom.com/childrewithdisabilities; Bonis in Issues Mental Health Nurs 37:153–163, 2016). The current study examined the effect of rational emotive family health therapy (REFHT) on parenting stress in families of children with autism spectrum disorders. A total of 128 participants allocated randomly to the intervention group and no-contact control group served as participants in this study. A 12-week REFHT programme that focused on reducing parenting stress was delivered to the intervention group by the therapists. Data analyses were completed using repeated-measures ANOVA. Results revealed no significant difference between the participants in the treatment group and no-contact control group at the initial evaluation. We found significant improvement in the management of parenting stress among parents of children with autism spectrum disorders after exposure to REFHT and at follow-up. Therefore, we concluded that rational emotive family health therapy has beneficial and sustained effects in improving the management of parenting stress among parents of children with autism spectrum disorders.