Objective: This research studies prevalence of reading disorder in third and fourth grade primary school students in Shahrekord (Iran). Method: In this cross-sectional study, 400 students were selected by cluster sampling. Reading level diagnostic scale was administered to the subjects and data analysis was carried out using descriptive statistic methods, and chi-square test. Results: results indicated that 10.5 and 8.4 percent of male, and 7.3 and 4.3 percent of female in grade four and three, suffered from reading disorder respectively. Difference between prevalence of reading disorder between female and male students was significant (p<0.05), and no significant difference was observed between prevalence of reading disorder between the two grades (p>0.05). Conclusion: The prevalence of reading disorder is high among primary school students in this city, and the bigger rate in males requires to be scrutinized.