Parental behavior management training is a critical element of mental health interventions for children with attention-deficit/hyperactivity disorder (ADHD). However, previous research has shown mixed results regarding the effectiveness of these training programs in reducing atypical behaviors in children with ADHD. The study aimed to investigate the effect of a parent training program on the parent-child relationship among parents of children with ADHD. This experimental study involved comparing two groups: an intervention group and a control group. Two questionnaires were used to collect data: one for demographic information and the other based on the work of Parker, Tupling, and Brown. All statistical analyses were performed using the SPSS version 21 software. The study showed that the parent training program significantly improved the parent-child relationship in families of children with ADHD, with a statistical significance level of P ≤ 0.05. This intervention positively influenced the development of the affected child. Parental behavior management training plays a vital role in improving the parent-child relationship in families of children with ADHD and can increase the overall quality of life for these families.