Background: The most important process in childhood and adolescence is learning. The purpose of this study was to determine the prevalence of dyslexia among primary male school students and the relationship between dyslexia, obesity and overweight.Methods: This is a cross-sectional study conducted on 1000 male students (first to fifth grade) in primary schools (20 schools) by using the multi-stage random sampling (50 students were selected randomly from each school). Data collection instruments were a weighting scale, a meter for evaluation of obesity and overweight and a reading inventory test for dyslexia. The height and weight were measured based on body mass index (BMI). Data were analyzed using SPSS17 by χ² test.Results: 17 and 28 percent of the students were obese and overweight in the first to fifth grades, respectively. On average, the percentage of dyslexia among the unhealthy students was 21 per cent; this rate was 3.5 per cent among the healthy students. In addition, χ² test showed that there was a significant difference between dyslexic and healthy students (P=0.001).Conclusion: The prevalence of dyslexia among students with overweight and obesity in comparison to healthy students is high; then close monitoring will ensure that these problems are minimized.