Objective To study the influence of tonsillectomy on resonance characteristics of four resonance cavity in patients with tonsil hypertrophy (II or III degree) .Methods Using multi-channel voice analysis system to test the cavity resonance characteristics and energy distribution of 38 tonsil hypertrophy male patients (including pre- and one month of post-operative) and 40 normal males when they speak /a:/.The frequency spectrum was 4 000 Hz(FR1 ,FR2 ,FR3 ,FR4 ) .Results FR2 ,FR3 energy values of the head cavity and mouth cavity ,and FR2 energy values of the thoracic cavity increased to the level of the normal control group after tonsillectomy(P<0 .05) .FR1 energy values of head ,mouth and thoracic cavity decreased to the level of the normal control group after tonsillecto‐my(P<0 .05) .FR1 ,FR2 ,FR3 ,FR4 energy values of laryngeal cavity maintained the normal level ,including pre- and post - operation .Conclusion Tonsillectomy makes oropharyngeal cavity volume expanded and airflow channel broaden .Tonsillectomy mainly maks high-frequency resonance of head and mouth cavities recovered to the normal level after about one month .