Objective: Apoptosis is a programmed cell death; it provides an important balance between lymphocytes in adenoid tissue. The aim of this study is to investigate the role of apoptosis in chronic adenoiditis and adenoid hypertrophy. This is the first study in the literature about apoptosis in adenoid hypertrophy and chronic adenoiditis. Methods: Prospective case-control study in a tertiary referral university hospital was conducted. 46 patients who had chronic adenoiditis and adenoid hypertrophy underwent adenoidectomy. Adenoids were evaluated for apoptosis and assembled into groups according to their size. Apoptotic cells were counted in three different microscopic fields and their average was taken for every microcompartment. As a result of immunohistochemical staining, specimens were compared for their apoptotic cell rate. Results: The difference in apoptosis of chronic adenoiditis and adenoid hypertrophy groups is statistically significant (p < 0.05). The age 6 was used as a cut-off to compare apoptosis in adenoid tissue. The difference was not statistically significant for patients at and below 6 years of age; however, the difference was statistically significant for patients above 6 years of age. The comparison of apoptosis in microcompartments of adenoid tissue (intrafollicular, interfollicular, subepithelial and intraepithelial) between chronic adenoiditis and adenoid hypertrophy groups revealed significant differences for intrafollicular and intraepithelial areas, and insignificant differences for interfollicular and subepithelial areas. Conclusion: Although apoptosis could not totally explain the pathogenesis of chronic adenoiditis and adenoid hypertrophy, it appeared to play an important role in it. Apoptosis functions to limit adenoid hypertrophy. Adenoid apoptosis appears to be age-dependent.