This work was carried out on 542 children aged from 9-12 years, who represent one fifth of all fourth grade pupils of the primary schools in Benha city. To diagnose dyslexia, all children included in the study were subjected respectively to: Picture Intelligence Test, silent reading test,measurement of visual acuity, hearing tests, neuropsychiatric and oral reading test and sentence comprehension were used to differentiate between different types of reading retardation. the dyslexic group was subjected to Stanford Binet intelligence test to assess accuretely the I.Q. the dyslexic group was eight out of 542 with a prevalence rate of 1.5% with ratio of 3:1 with male preponderance