Objective: This research studies emotional disorders that influence dyslexia in elementary students. Method: Initially, through a random multi-stage cluster sampling, 105 students suspected of having dyslexia were chosen from third, forth and fifth graders in Tehran. Then, 70 students were selected after evaluation by diagnostic tests including Wechsler’s Intelligence Scale, and Reading Disorders Test. Rutter’s Behavioral Questionnaire was used to assess co-morbid behavioral disorders. Backward regression was used to determine the extend to which each predictor factor contributes to the prediction of target variables. Target variable consisted of reading accuracy, speed and comprehension while predictor variables consisted of anxiety-depression, hyperactivity-aggression, attention deficit, social maladjustment and antisocial behavior. Results: Findings indicated that depression-anxiety, hyperactivity, aggression and attention deficit played a significant role in predicting dyslexia and its factors (reading speed, accuracy, and comprehension). Conclusion:  Accordingly, therapeutic programs for dyslexic children with co-morbid emotional disorders are stressed.