Objective Changes in vocal patterns after adenotonsillectomy are questionable. Few studies have assessed acoustic voice changes before and after adenotonsillectomy. The objective of this study wasto evaluate the impact of adenotonsillectomy on the voice of children with adenotonsillar hypertrophy. Participants and Methods The study included fifty children ranging in age between 4 and 12 years, with adenotonsillar hypertrophy, indicated for adenotonsillectomy. Auditory perceptual assessment of speech included nasality, degree of hyponasality, degree of open nasality, and degree of dysphonia. Acoustic analysis was carried out before and after one month and three months of surgery, using multidimensional voice program software (MVDP). The vowels were analyzed as to their acoustic parameters: fundamental frequency (Hz), jitter (%), shimmer (dB) and noise-harmony ratio (NHR; dB). Results At oneand threemonths after surgery, preoperative readings were of F0 score while jitter and shimmer normalized only at the 3^rd month. There were significant differences between readings at one month and threemonths of F0 and jitter. Auditory perceptual assessment(APA) of voice (dysphonia) and APA of speech (hyponasality) significantly improved at 1^st and 3^rd month after surgery with significant differences between results of 1^st and 3^rd month. Harmonic noise ratio (HNR) had negative, significantly fair correlation with APA of Voice (dysphonia).  Conclusion Hyponasal speech and with dysphonia preoperatively often have normal resonance and voice following adenotonsillectomy. Objective and subjective evaluation of speech and voice can help the specialist in the management of patients with adenotonsillar hypertrophy.