The study was carried out in a group of 285 children and adolescents aged 4-20 yrs. Children were divided according to their main disease: group with obesity, obesity and coexisting hypertension, hypertension and diabetes. Each group was divided into children with positive or negative family history of cardiovascular diseases. We assessed routine lipid parameters, body mass index and new atherosclerosis risk factors: lipoprotein (a), apolipoproteins A-I and B, homocysteine, fibrinogen, t-PA and PAI-1. Positive family history of cardiovascular diseases was found in 28% families, and in 8% families it was premature cardiovascular disease. In 48% children we found hypertension in family. Children with positive family history had significantly higher body mass index (25.4 vs 23.8 kg/m2). In the group with obesity and hypertension we found significantly higher cholesterol (182 vs 160 mg/dl) and LDL-cholesterol level (114 vs 93 mg/dl). Lipoprotein(a) level was significantly higher in children with positive family history (38 vs 28 mg/dl). Significant differencies were also found in apolipoprotein B level (90 vs 84 mg/dl). In logistic regression analysis only BMI and lipoprotein(a) were significant in predicting future cardiovascular events in children. Obese, hypertensive and diabetic children often come from families with cardiovascular diseases. Hypertension is the most often prevalent atherosclerosis risk factor in families. Children with positive family history of cardiovascular diseases have significantly higher body mass index. Out of new atherosclerosis risk factors lipoprotein(a) and apolipoprotein B may have real value in predicting future cardiovascular disease in the child. The aim of the study was to compare obese, hypertensive and diabetic children with positive and negative family history of cardiovascular diseases. In the work we have tried to find which of the new atherosclerosis risk factors may have the real value in predicting future cardiovascular events in children already predisposed to atherosclerosis.