Background: ADHD is one of the neurodevelopmental(NDs) disorders, that can effect on executive functions of the brain, so it is important to have a valid psychodiagnostic to measure this disorder. The Brief Executive Functions Questionnaire(BRIEF) is one of these tools. In the present study, the aim of this research is to investigate the diagnostic validity of this tool in diagnosing students with attention deficit disorder. Methods: The current research is Cross-sectional applied research and standardization. The target population is students between 9 and 15 years old in Tehran who affected by attention deficit hyperactivity disorder. The sample size was selected based on the formula, which includes 58 people. Finding: In this study we found emotional control organization of material has not diagnostic validity because confidence interval was less than one and two standard deviations(47/36)(49/50). Sensitivity coefficient were (0.40)(0.36). The amount of experimental and critical difference were (0.75)(0.68). Conclusion: According to the present research, the scale of executive functions of BRIEF in students with attention deficit disorder in the scales of inhibition, transition, planning, monitoring, working memory and initiation has diagnostic validity according to the distribution diagram of the sensitivity coefficient and confidence interval, as well as the scales of emotion control and organization of materials has not diagnostic validity, thus the current tool in terms of scales that have diagnostic validity can help us in measuring it in people with ADHD.