en Nutrition Nutrition پژوهشي Research <strong>Background and Objectives: </strong>To study associations in diet quality academic performance and weight status in urban adolescent high-school students.<br> <strong>Materials and Methods: </strong>This study was a cross-sectional study in high schools in Tehran, Iran. A total of 629 students (317 boys and 309 girls), aging 17&ndash;19 years, from 49 high schools participated in the study. Dietary intake was measured using two 24-h recalls. Diet quality was measured using Healthy Eating Index-2015. Academic performance was assessed by evaluating scores achieved in national exams at the end of high-school junior year. Standard anthropometric measurements were used. Linear and multinomial regressions were used to assess the associations between weight status, diet quality and academic performance.<br> <strong>Results: </strong>Student&rsquo;s scores in grammar and literature were significantly associated to diet quality (<em>p </em>< 0.05). After adjusting for sex and other socioeconomic confounders, the association was non-significant. Significant differences were seen in weight status between boys and girls; however, such differences were not based on the prosperity levels in weight statuses. The overall frequency of overweight was nearly 24%, while obesity was twice in boys (nearly 26%), compared to girls.<br> <strong>Conclusions: </strong>Findings verify needs of policies to improve student diet quality, leading to better health and educational achievements. Further studies are needed to investigate associations between diet quality and academic performance. Diet quality, Weight status, Academic performance, Adolescents 27 33 http://nfsr.sbmu.ac.ir/browse.php?a_code=A-10-921-1&slc_lang=en&sid=1 Mohammad Reza Mazandaranian r.mazandaranian@gmail.com 10031947532846004988 10031947532846004988 No Department of Community Nutrition, National Nutrition, and Food Technology Research Institute, Faculty of Nutrition and Food Technology, Shahid Beheshti University of Medical Sciences and Health Services, Tehran, Iran. Nasrin Omidvar omidvar.nasrin@gmail.com 10031947532846004989 10031947532846004989 Yes Department of Community Nutrition, National Nutrition, and Food Technology Research Institute, Faculty of Nutrition and Food Technology, Shahid Beheshti University of Medical Sciences and Health Services, Tehran, Iran. Hassan Eini-zeinab hassan.eini@gmail.com 10031947532846004990 10031947532846004990 No Department of Community Nutrition, National Nutrition, and Food Technology Research Institute, Faculty of Nutrition and Food Technology, Shahid Beheshti University of Medical Sciences and Health Services, Tehran, Iran. Azam Doustmohammadian Doost_mohammadi@yahoo.com 10031947532846004991 10031947532846004991 No Gastrointestinal and liver disease research center, iran university of medical sciences, tehran,iran Marziye Ashoori ashoori177@yahoo.com 10031947532846004992 10031947532846004992 No Department of Community Nutrition, National Nutrition, and Food Technology Research Institute, Faculty of Nutrition and Food Technology, Shahid Beheshti University of Medical Sciences and Health Services, Tehran, Iran. Behnaz Abdar-Esfahni esfahani.b.a@sbmu.ac.ir 10031947532846004993 10031947532846004993 No Department of Community Nutrition, National Nutrition, and Food Technology Research Institute, Faculty of Nutrition and Food Technology, Shahid Beheshti University of Medical Sciences and Health Services, Tehran, Iran. Omid Hosseini-Mousavi seyedomidhosseini71@gmail.com 10031947532846004994 10031947532846004994 No Department of Community Nutrition, National Nutrition, and Food Technology Research Institute, Faculty of Nutrition and Food Technology, Shahid Beheshti University of Medical Sciences and Health Services, Tehran, Iran.