We evaluated the serum concentrations of zinc, copper and selenium in 125 patients with juvenile chronic arthritis (JCA). Trace element levels showed distinct abnormalities as compared with those of a large group of healthy children. Serum zinc and selenium concentrations were lower and those of copper higher in children with arthritis than in healthy children and, further, patients with polyarthritis had significantly higher copper and lower zinc levels than those with oligoarthritis. Serum zinc levels showed a direct correlation with hemoglobin and an inverse correlation with values for the erythrocyte sedimentation rate (ESR), whereas copper correlated directly with ESR. Selenium values did not correlate with the activity of the disease, but were low in the patients with arthritis of long duration.