Adult rheumatoid arthritis (RA) is the most common of rheumatoid diseases, that may cause hand dysfunction in some patients. Its equivalent in children is juvenile chronic arthritis (JCA). The aim of our study was to evaluate differences in hand deformity between children with JCA and adults with RA. The prospective study was performed on two groups of patients: 15 with JCA (average age 13.1 years, range from 9 to 18 years) and 15 with RA (average age 53.6 years, range from 42 to 60 years). Both groups were similar in terms of Seyfried classification system and duration of the disease--7.9 years for children and 8.6 for adults. Clinical assessment was performed according to Swanson and Seyfrieda classification system. Patients with RA had only radial wrist "deviation" and those with JCA had both radial and ulnar wrist deviation. In MCP joints in adult's group fingers were always in ulnar position and in children's group finder position was opposite to wrist position. "Swan neck" deformity of fingers from II to V was found in both groups. "Buttonhole deformity" was more often seen in older group. Pain of wrist and in IP joints was more often found and was more severe in RA group. Hypertrophy of synovium and subluxation of IP and wrist joust were found with similar frequency in both groups. In other joints subluxation was rare. Concluding, radial wrist deviation is typical for RA patients. Children with JCA had both radial and ulnar wrist deviation. In MCP joints deformity is always opposite to wrist deviation.