Bone demineralization often accompanies juvenile chronic arthritis (JCA). Fourteen patients with confirmed diagnosis of JCA had their bone mineral density (BMD) measured with the use of dual photon X-ray absorptiometry. The results obtained were compared to the Lunar BMD DPXA standards. Seven patients received Prednisone in doses of more than 0.16 mg/kg/day for more than 6 months and 7 patients (sex and age matched) never received any steroids at all. In the first group BMD was decreased in 7 patients (100%), in the second group BMD was mildly decreased in 2 patients (28%). Due to the difference in BMD in both groups, it is obvious that corticosteroids have substantial influence on bone demineralization in JCA.