Intercellular adhesion molecule-1 (ICAM-1) is a membrane bound molecule that is involved in cell to cell adhesive interactions within the immune system. The aim of this study was to measure the concentrations of soluble ICAM-1 (s-ICAM-1) in 25 HIV-1 infected pediatric patients. We compared s-ICAM-1 values to parameters of immune activation--such as IgA and beta 2 microglobulin (beta 2 m) and viral replication such as adenosine deaminase (ADA). s-ICAM-1 levels were found to be significantly increased in HIV-1 infected children when compared with healthy controls. Levels of s-ICAM-1 were higher in patients with severe forms of HIV-1 infection in comparison with those with a mild form of the disease or non symptomatic infection. No differences in titers of s-ICAM-1 were recorded between seroreverters and healthy controls. A positive correlation between levels of s-ICAM-1 and IgA, beta 2 m or ADA concentrations was detected. Similarly, there was statistically significant correlation between levels of IgA, beta 2 m or ADA. In conclusion, increased s-ICAM-1 levels in HIV-1 pediatric patients appeared to be another important feature among the immune disturbances triggered by HIV-1 infection. s-ICAM-1 might be involved in the development of the immunologic dysfunction during the progression of the disease.