Aim of study consists of establishing of some clinical-biological correlates for rheumatic fever (RF) in children, namely correlations between clinical status and lipoperoxidation products -- malonidialdehide (MDA) and antioxidative enzymes in the blood. In the neutralization process of superoxside anions ceruloplazmin (CP), catalase (CAT) and transferin (TF) are key antioxidant enzymes (AOE) of antioxidative defense system (AOD). We studied 38 patients 3-15 years of age with different variants of RF. We measured the levels of MDA, CAT, CP, TF in the plasma in patients with acute rheumatic fever (ARF) and chronic rheumatic heart disease (CRHD). In all of our cases AOE (CAT, CP, TF) were high at time of diagnosis, concomitant with increased MDA and inflammatory tests. Our study revealed intensified activity of AOD enzymes in children with RF.