Introduction. The metabolic syndrome (MS) in association with increased left ventricular myocardial mass (LV Mass), LV myocardial mass index (LVMI), LV hypertrophy (LVH) is an important risk factor for cardiovascular diseases which occur in childhood. Aim of the study. Study of the MS's influence on LV Mass, LVMI and cardiac remodeling in the hypertensive pediatric population. Materials and methods. 60 children aged 10 - 18 years were enrolled in the study. Study group included 22 children with MS, and the control group - 38 children with pre-MS. The diagnosis of MS was established according to the International Diabetes Federation criteria (IDF, 2007). Respondents were examined through transthoracic echocardiography. Results. According to the IDF criteria, MS was confirmed in 36.4%, pre-SM at 63.6%. LV Mass: pre-SM - 151.4±56.2, score Z - 0.15±0.9, those with SM - 167.3 ± 48.8, score Z - 0.24±1.3. LV Mass > 95th percentile was in ≈ 20% of the pre-MS group and in ≈ 45% in patients with MS. LVMI in the control group - 36.3±8.4 vs baseline - 38.7±10, LVMI>95th percentile was determined in ≈ 15% vs ≈ 35%. Left ventricle posterior wall relative thickness: 0.39±0.05 vs 0.42±0.05. In the left ventricle: normal stare 55.5% (MS) vs 80.4% (pre-SM), concentric hypertrophy 30.4% vs 5.2% concentric remodeling 8.1% vs 4.7% eccentric hypertrophy - 6 % vs 9.7%. Of all MS components, AHT in 60% of cases was associated with LVMM and VS hypertrophy in the working group and 40% in the control group. Conclusions. All of the MS components, AHT was more often associated with LV, LVM index, LV hypertrophy, especially among the boys.