Background and Purpose: Play therapy is an innovative psychotherapy technique in child therapy. This therapy can fulfill the needs of children in different ages and it can significantly affect their behavior change, adaptability, and social skills. Present study aimed to compare the effectiveness of individual and group play therapy on the coping behaviors of students with Attention Deficit Hyperactivity Disorder (ADHD). Method: This study was an experimental research with pretest-posttest control group design. The study population included all the male and female students with ADHD in Tehran in the academic year 2018-2019. A sample of 60 students was selected by purposive sampling and then randomly assigned to either the experimental or control group (20 per group). The experimental group underwent ten 45-min sessions of individual play therapy and ten 60-min sessions of group play therapy, but the control group received no intervention. Oppositional Behaviors Questionnaire (Falahi et al., 2017) and Conner's ADHD Rating Scale (1999) were used to gather the data. Data were analyzed by ANCOVA. Results: Findings showed that both individual and group play therapy were effective in increasing the component of problem coping (F=217.93), decreasing the component of solution aversion (F=1153.09) and destructive coping (F=317.57) in primary students with ADHD (p<0.01). Also, based on the findings of follow-up test, group play therapy was more effective than individual play therapy in terms of increasing the component of problem coping (MD=-3.61) and decreasing the components of solution aversion (MD=4.65) and destructive coping (MD=3.66) in primary school students with ADHD (p<0.01). Conclusion: Individual and group play therapy are effective in increasing the coping behaviors of primary school students with ADHD but based on the results, group play therapy can be more effective in improving the mental and behavioral situation of children.