The role of ACE gene insertion (I) or deletion (D) polymorphism on blood pressure phenotype is not clear in children. The aim of this work is to examine the association between hypertension and ACE I/D polymorphism, as well as the contribution of clinical and metabolic parameters on blood pressure. The study participants were 199 obese children. Forty-four of them were hypertensive. The hypertensive subjects were older than the normotensive and most of them were pubertal. The prevalence of hypertension in obese subjects with II, ID, and DD genotype was similar. There was no difference between the hypertensive and the normotensive group according to ACE I/D genotype, BMISDS, sex, blood glucose level and total cholesterol levels. In obese children, high IR-HOMA values, puberty, presence of family history for hypertension, hypertriglyceridemia, and low HDL-cholesterol, high triglyceride/HDL-cholesterol ratio were found as increased risk factors of hypertension. In obese children and adolescents, blood pressure did not differ by ACE I/D genotype. The presence of family history, puberty, insulin resistance and hypertriglyceridemia constitute important risk factors for developing hypertension.