Research objective was studying parameters of Kayser-Fleischer's rings (KFR) in patients with Wilson disease (WD). KFR were examined with slit lamp and were photographed using digital camera. KFR expression was wmeasured as a ratio of ring area and сornea area on the photograph. KFR sizes were 0.17 – 0.68 in 62(86%) patients ith WD. At follow up examination KFR sizes were 0.14 – 0.52.