The objective of the study was to determine the effect of the maxillary sinus on the voice. The prospective study was conducted at an academic secondary referral center. A prospective chart review of 43 patients (17 males, 26 females) who conducted a voice recording and survey before and 3 months after middle meatal antrostomy whose lesion was confined to the maxillary sinus. Subjective voice changes were surveyed using a questionnaire. After phonation [∧m ma: the Korean pronunciation of 'mother'], [Nu Na: the Korean pronunciation of 'sister'], we analyzed the nasal consonant [m] of [∧m ma] and nasalized vowel [a] of [∧m ma] and [a] of [Nu Na]. In the poll conducted, the change rates for males and females were 41.1 % (7/17) and 15.4 % (4/26), respectively; of the male patients, 85.7 % (6/7) felt that the sound quality was better and 14.3 % (1/6) that it was worse. However, all the female patients felt it was better. Among of the patients with an improved voice, reduced nasal sound was the most frequent observation. In an objective analysis, a tendency to lowered frequencies was observed for nasalized vowels after surgery. Significant differences were observed at second formant frequencies of [a] of [∧m ma] and first formant frequencies of [a] of [Nu Na] in female subjects (P < 0.005). Our findings indicated that the maxillary sinus plays a role in the modification of voice quality. Preoperative counseling is important for patients concerning expected changes in the voice after maxillary sinus surgery.