Objective: This study aimed to investigate the incidence of Actinomyces in tonsillar tissues of patients undergoing tonsillectomy and to determine the association among tonsillar volume, preoperative antibiotic use, and presence of Actinomyces in tonsil tissues.Methods: In this study, 142 patients who underwent tonsillectomy in last four years were included. Of the total patients, 97 (66. 9%) were children and 47 (33.1%) were adults. The patients' age, sex, preoperative antibiotic use, tonsillar volume, and presence of actinomyces in tonsillar tissues were recorded.Results: Actinomyces was identified in tonsillar tissues of 16 (16.4%) pediatric and 21 (44.6%) adult patients. Of all pediatric patients positive for Actinomyces, 13 were males and three were females whereas of all adult patients positive for actinomyces, 14 were males and seven were females. Tonsillar tissue volumes in both pediatric and adult patients positive for Actinomyces were statistically higher than the Actinomyces negative ones. Antibiotic use was higher and the incidence of Actinomyces was lower in pediatric patients than in adult patients positive for Actinomyces.Conclusion: Our study results revealed that Actinomyces was prominent in adult patients with tonsillar hypertrophy. In addition, the frequent use of antibiotic decreased the incidence of Actinomyces in tonsillar tissues.