Introduction: Studies have shown that interactions between parents and children and whole family played significant role in formation and intensification of children's behavioral - emotional vulnerability.

Parenting Styles are one of the important elements in the family's system styles that can affect the development of children. Present study is aimed to investigate effectiveness of child-parent relationship therapy based on discipline styles of mothers' parenting of children 8 to 11 years old with attention deficit hyperactivity disorder (ADHD).

Method: This study is quasi experimental research based on pretest-posttest with control group that statistical population (69 pair of mother-child with ADHD), 30 pair of mother-child with ADHD were assigned into experimental and control groups randomly.

Experimental and control groups were assessed by Arnold's parenting questionnaire in 2 stages. The collected data were analyzed by using multivariate analysis of covariance (MANCOVA).

Results: The results showed reduction (improvement) significant statistically in dysfunctional disciplinary models and changes in mothers' parenting (except procrastination) in experimental group or parent-child relationship-based intervention compared to the control group.

Conclusion: It can be concluded according to the findings of this study and consideration of previous research that  these interventions has advantage in the reform of parenting styles Iranian mothers of children with ADHD