Introduction/Objective. Tonsillitis is a very common condition found in the pediatric population but also in adult patients. One of the consequences of such conditions is poor voice quality. Hoarseness, poor voice impostation, interruption, and hypernazalization are just some of the differences in patient voice quality. The objective of this paper was to examine the effects of tonsillectomy on the voice quality. Methods. The sample included 37 patients, 17 female and 20 males, ranging in age from 3 to 39 years. The method involved recording patients a month before and a month after tonsillectomy with a digital sound recorder and were analyzed in the Praat program. The variables monitored in the basic voice are: voice pitch, standard deviation of voice, degree of voice interruption, Jitter, Shimmer, and signal-to-noise ratio. In the statistical analysis, in addition to standard descriptive analyzes, t-test and ACNOVA were also used. Results. The results show that there are effects of tonsillectomy on SD of baseline voice (p = 0.002), Shimmer (p = 0.002) baseline voice interruption rate (p = 0.023), signal to noise ratio (p = 0.003). There were no differences in the effects of tonsillectomy with respect to the gender of the subjects. Conclusion. Based on the conducted research, there were some methodological conclusions that could be considered as a recommendation for future research: increase the number of persons in the sample, introduce a variable of chronological age, type of surgical intervention and gradation of size of the tonsil and adenoid tissue. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 179055]