Background: The vocal tract, which starts from the glottis and extends to the lips is considered as resonator for speech production. Enlarged palatine tonsils may cause hypernasal speech, oral breathing or muffled voice. Adenotonsillectomy is the most common surgery performed by otolaryngologists especially in children. To assess different possible surgical factors of adenotonsillectomy that can affect speech and voice of children with hypertrophy palatine tonsils and nasopharyngeal adenoid. Methods: The study is a prospective study that was done on 100 children selected randomly, ranging in age between 3-13 years, all the cases were suffering from recurrent attacks of pharyngitis ,fever ,nasal obstruction and mouth breathing indicated for adenotonsillectomy in the department of otorhinolaryngology El-Minia University hospital. Results: Children were under gone adenotonsillectomy operation either by diathermy or surgical techniques show no significant different effect on their voice postoperatively. Conclusion: Regardless of  different techniques of adenotonsillectomy as diathermy or surgical technique could cause different in the voice and speech postoperatively in children.