High values of plasma homocysteine (Hcy) level were highlighted and in the child obesity, elevated levels can be an independent risk factor for cardiovascular disease. Objective. Research of plasma Hcy values in overweight and obese school children compared with a control group of non obese children and without cardiovascular diseases and correlations with blood pressure values and blood levels of total cholesterol and tryglycerides. Methods. The authors researced in ambulatory 36 children (8–18 years) of which 26 overweight and obese and 10 non-obese healthy children, without cardiovascular diseases. All children were investigated by clinical exam, body mass index, determination of plasma levels of homocysteine in the morning after 12-hour fasting, total cholesterol, tryglyceride, bloog glucose. Results. Plasma levels of homocysteine were elevated in children with obesity, 42,18% of cases, compared to the control values (the mean 8,98 ± 1,73 μmol/ vs 6,1 ± 2,4 μmol/l). Increased levels of homocysteine in obese children was correlated with body mass index and more important to the in obese children with hypertension (5 cases). Elevated Hcy were often associated with high total cholesterol ± triglycerides in obese children compared with control values, normal values of blood glucose. Conclusions. Obesity in school children and especially association and the presence of high blood pressure werw associated with an increase in plasma homocysteine values often correlated with elevated total cholesterol ± triglyceride levels. Research and systematic monitoring of values of plasma homocysteine correlated with cholesterol and triglyceride levels allows an objective estimation of cardiovascular risk in children with obesity and an indication for cardiovascular prevention effective measures.