The aim of the study was to investigate the prevalence of generalized periodontitis depending on age and biotype of periodontium. Materials and methods: We examined 855 males aged 20-55 years, who were divided into 2 groups: the main group - 570 surveyed with a generalized periodontitis, the comparison group - 285 dental healthy individuals.The diagnosis of generalized periodontitis was established by the classification Danilevsky M.F. (1994) and refined by using paraclinical indices. The periodontal biotype was determined using Hu-Friedy Colourvue Biotype Probe. Results: As a result of the conducted researches was establish, in the carriers of blood group O (I) and A (II), developed forms of generalized periodontitis were found, on average, 2.7 times more often than the initial forms of the disease. Instead, at the representatives of B (III) and AB (IV) groups blood the frequency of initial GP - I degree was on average, 1.2 times greater than the prevalence of developed forms of generalized periodontitis. Also as a result of our researches, we found that the cluster A1 had 39.30% patients, cluster A2 was found at 28, 77%, and cluster B - 31.93% of the total number of patients with generalized periodontitis. Conclusions: As a result of our research, it was found that in the carriers of the blood group O (I) and A (II), more advanced forms of generalized periodontitis were observed, which was confirmed by the presence of the biotype of the periodontal disease in the cluster A1 and A2.