To investigate the changes of insulin resistance and soluble intercellular adhesion molecule-1 (sICAM-1) in normotensive adolescents with a family history of hypertension (FH) and to analyse the related factors. The study included 142 normotensive adolescents aged 13-15 years. On the basis of an FH, the samples were divided into positive FH (FH(+) group) and negative FH groups (FH(-) group). Anthropometric measurements included height, weight, waist circumference (WC) and blood pressure (BP). Blood samples were collected and fasting plasma glucose (FPG), serum lipids, true insulin (TI) and sICAM-1 were assayed. The FH(+) group had significantly higher levels of FPG, TI, homeostasis model assessment of insulin resistance (HOMA-IR) and sICAM-1 than the FH(-) group (P<0.01). HOMA-IR showed positive correlation with body mass index (BMI; r=0.405), WC (r=0.416), systolic BP (SBP; r=0.165), FPG (r=0.427), triglyceride (r=0.195), TI (r=0.993) and negative correlation with high density lipoprotein cholesterol (r=-0.196) (P<0.05). sICAM-1 showed a positive correlation with triglyceride (r=0.239, P<0.01). In multiple linear regression analysis, WC (beta=0.024, P=0.000) and FH (beta=0.467, P=0.000) were significant independent predictors for HOMA-IR, and triglyceride (beta=0.328, P=0.007) and FH (beta=0.395, P=0.016) were significant independent predictors for sICAM-1. These results indicate that insulin resistance and endothelial activation were found in normotensive adolescents with an FH. We should make great efforts to alleviate the insulin resistance and endothelial activation by diet and exercise, and it would reduce the incidence of hypertension in adolescents with an FH.