The aim of this study was to evaluate serum lipid abnormalities, particularly lipoprotein (a), [Lp(a)] as an independent risk factor for cardiovascular disease in children with mild and moderate renal failure. Study were performed on 14 children of whom serum creatinine levels were above 265.3 mumol/l and 32 patients with serum creatinine levels below 265.3 mumol/l. Control group consisted of 27 healthy age-matched subjects. All children were tested for concentration of serum Lp(a), total cholesterol (TC), triglycerides (TG), low density lipoprotein cholesterol (C-LDL) and high density lipoprotein cholesterol (C-HDL). It was found a significantly increase in Lp(a), TC, C-LDL and significantly decrease in C-HDL in children with more advanced renal insufficiency compared to the control. In children with mild renal failure concentration of serum Lp(a) also increased but not significantly. Patients in this group had elevated serum TC and decreased C-HDL. These results suggest that even in the early stages of renal insufficiency in children abnormalities of lipoprotein are present. Such abnormalities, particularly Lp(a) might contribute to accelerated atherosclerosis in this patients.