Background: The speech disorders may produce irreparable damage to childs speech  and language development in the psychosocial view. The voice, speech sound production and fluency disorders are speech disorders, that  may result from delay or impairment in speech  motor control mechanism, central neuron system disorders, improper language stimulation or voice abuse.

Materials and Methods: This study examined the prevalence of speech disorders in 1393 Arakian students at 1 to 6th grades of primary school. After collecting continuous speech samples, picture description, passage reading and phonetic test, we recorded the pathological signs of stuttering, articulation disorder and voice disorders in a special sheet.

Results: The prevalence of articulation, voice and stuttering disorders was 8%, 3.5% and%1 and the prevalence of speech disorders was 11.9%. The prevalence of speech disorders was decreasing with increasing of student’s grade. 12.2% of boy students and 11.7% of girl students of primary school in Arak had speech disorders.

Conclusion: The prevalence of speech disorders of primary school students in Arak is similar to the prevalence of speech disorders in Kermanshah, but the prevalence of speech disorders in this research is smaller than many similar researches in Iran. It seems that racial and cultural diversity has some effect on increasing the prevalence of speech disorders in Arak city.