Wilson-Konovalov disease is a rare autosomal recessive genetic disorder in which copper accumulates in the liver, brain and other target organs. The paper describes a family case of the abdominal form of the disease in three sisters, the eldest of them died from fulminant liver failure at the age of 18 years. The second sister aged 16 years was diagnosed as having the disease at the stage of decompensated liver cirrhosis; her treatment with D-penicillamine resulted in complete disease remission. The youngest sister was diagnosed with the disease at the preclinical stage, which could expect its good prognosis. However, the patient’s refusal of treatment led to death from liver failure. This case demonstrates the importance of timely diagnosis and the possibility of dramatic improvement in prognosis even at the stage of decompensated liver cirrhosis.