Objective: to learn interconnection of obesity, abdomen overweight and blood pressure (BP) among adolescents with 12–13 years Design and method: Cross-sectional study. Adolescents were evaluated at their schools after parent consent. There were included in the study 1473 (middle age, SD 12,1 ± 0,002). Age, gender, nationality, BP, height, weight, abdominal circumference (AC), body mass index (BMI). BP was measured three times by oscilometric method and high BP was defi ned as systolic BP (SBP) and/or diastolic BP (DBP) > = p95 for age, gender and height percentile; O/O as BMI > = p85 for gender and age; and increased AC as > = p90 for age and gender. Results: 1473 adolescents were evaluated (48,8% males). The prevalence of elevated BP was 12,6%. For comparison, according to ethnicity, the two most numerous groups were identified, of which the Kazakh population was 87% (n = 1282) and Russian 13% (n = 191) adolescents. By weight, BMI, SBP, DBP, AC revealed statistically significant differences (p < 0,001). According to the study in the boys’ population, the following data were found in the structure of individuals with normal BP for BMI: overweight in 4, 7% (n = 59), obesity in 0,7% (n = 9). In the structure of individuals with hypertension in boys, the BMI score was: overweight 19,4% (n = 36), obesity in 1,6% (n = 3). In the Kazakh population, a statistically significant difference was noted in boys (chi square Pearson = 39,49, df = 4, p < 0,001), as well as in girls (chi square Pearson = 33,99, df = 4, p < 0,001). In the Russian population, the girls had a statistically significant difference (chi square Pearson = 34.0, df = 4, p < 0.001). Conclusions: Prevalence of elevated BP in a population of 12 to 13 years-12,6%. In both groups statistically significant differences in BMI, SBP, DBP, AC parameters were revealed. In the Kazakh population of both sexes and girls of the Russian population, statistically significant differences in the structure of BMI distribution in groups with normal BP and were revealed.