Background and Purpose: Attention Deficit Hyperactivity Disorder (ADHD) is one of the most prevalent childhood disorders which can affect children’s academic achievements and performance. The purpose of the present study was to compare the academic achievement in elementary students with and without Attention Deficit and Hyperactivity Disorder in Tehran, Iran.

Method: Present study had causal-comparative design. The study population consisted of all elementary students in the city of Tehran. Sample consisted of 160 third to fifth elementary school students (80 students with ADHD and 80 students without ADHD) who were selected using random sampling method. For diagnosis of ADHD, the 18-item ADHD checklist (Ghanizadeh & Jafari, 2010) was completed by the teachers. Academic achievement of two groups was calculated using students’ GPA on four courses (Persian, Writing, Math, and Science) in previous academic years. Independent sample t-test was used for data analysis.

Results: Results indicated that ADHD group had a significantly lower academic achievement comparing to normal group (p < .01). In addition, female students with ADHD showed higher academic achievement comparing to male students with ADHD (p < .05).

Conclusion: In order to prevent academic wastage among elementary students with ADHD, early identification and treatment of such children is recommended.