The aim of this study was to investigate the relationship between sialoglycoproteins and the lipoprotein profile in a group of children with different levels of low-density lipoprotein cholesterol. We have studied 177 children of 132 families who were sent to our Pediatric Lipid Research Clinic because of serum cholesterol concentrations higher than 5.17 mmol/l. At the time of diagnosis, we analyzed the serum lipoprotein profile and the sialoglycoproteins: alpha 1-antitrypsin, acid alpha 1-glycoprotein, haptoglobin, alpha 2-macroglobulin, transferrin, IgA, IgG, IgM, complement C3 component and ceruloplasmin. At 7.0 to 10.9 years, alpha 1-glycoprotein serum concentrations were higher in the high risk group than in the moderate risk group (P < 0.05). At 2.0 to 6.9 years, IgA and IgM serum concentrations were higher in the moderate risk group than in the low risk group (P < 0.05 and P < 0.01, respectively), and IgG and IgM serum concentrations were also higher in the high risk group than in the low risk group (P < 0.05). Our results seems to reflect a general reaction to injury or inflammation which could be associated with the atherosclerotic process.