The article discusses the pathophysiological mechanisms of the relationship between inflammatory periodontal diseases and metabolic syndrome (MS). Clinical and biochemical assessment of the dynamics of indicators of lipid blood profile, carbohydrate metabolism and oxidative stress has been conducted in patients with periodontal disease and MS. We examined and treated 73 patients aged from 35 to 55 years with clinical and biochemical features of the MS (body mass index (BMI) >25 kg/m2, abdominal type of obesity, impaired glucose tolerance and atherogenic dyslipidemia). According to the data obtained, the inclusion of probiotics and antioxidant in the complex therapy on the background of the reduced low-carbohydrate diet and increased physical activity in MS patients contributed to the correction of atherogenic blood plasma indexes, normalization of carbohydrate metabolism, cupping effects of oxidative stress, improvement of reparative processes in periodontal tissues, more pronounced than in patients receiving standard treatment (control). After treatment at 24 weeks BMI decrease by 8.6% (from 32.7±0.8 to 29.9±0.6 kg/m2) mainly due to the reduction in fat mass (by 23%) has been observed in the whole group of patients with MS. The HOMA IR index decreased in patients of the main group by 31.8% while in the control group - only by 8.5% (p<0.001), fasting immunoreactive insulin level - by 13 vs 4.5% (p<0.001), insulin C-peptide level - by 36.8 vs 21.6% (p<0.01), glycated hemoglobin - by 13.0% versus 4.7% (p<0.01), malondialdehyde - by 47.8 vs 25.8% (p<0.01). Levels of total cholesterol, triglycerides and low-density lipoproteins decreased in patients of the main group by 13.0; 30.8 and 19.0%, respectively, while in the control group the decrease was lower and amounted to 4.7; 25.0 and 14.6% (p<0.05-0.01).