Patients with chronic rheumatic heart disease are at highest risk of infective endocarditis. Poor oral hygiene is main reason for developing of periodontal diseases and it is a known as a risk factor which can lead to infective endocarditis in CRHD patients. Therefore, it is important to determine the prevalence and severity of periodontal diseases in these patients. During 2014-2018 years, at the Department of Therapeutic Dentistry FPGE, Ukraine, we examined 719 patients and their histories of disease who had diagnosted CRHD, of which 473 women and 246 men, the average age of the surveyed was 52,89±13,61 year old. A dental examination was conducted using periodontal screening and recording (PSR) index. The prevalence of periodontal disease was 91,38±1,05%. The proportion of people with total periodontal health (code “0”) was 8,62±1,05%, 14,6±1,32% exhibited bleeding on probing of the sulcus (code “1”), calculus (code “2”)was detected in 24,48±1,60% and probing depths between 3,5-5,5 mm were in 32,96±1,75% (code “3”), probing depth of 6 mm and deeper (code“4”) were measured in 19.33±1,47%.Code “*” which means special periodontal problems (recession, tooth mobility,furcation involvement) wasin 46,73±1,86%. Due to PSR index we have established high incidence of periodontal disease. About 72% of patients with CRHD could be treated by oral hygiene instruction and scaling, the remaining 19,33% required more involved therapy, including surgery. Those are the invasive methods of periodontal treatment, which may be the cause of bacteremia and, as a consequence, infectious endocarditis and aggravation of the underlying disease. Therefore, early detection and diagnosis are key elements in the prevention of periodontal diseases in CRHD patients. Use of PSR index allowed to establish a prevalence of periodontal diseases and predict the periodontal treatment needs of patients with CRHD.