There is a genetic problem in living donor liver transplantation, involving Wilson's disease, because the majority of donors have a kinship relationship. Recently, it was reported that the serum ceruloplasmin level is insufficient in some persons with one allele mutation. The recipient was a 13-year-old male child, and the donor was a 22-year-old woman, who was his sister by a different father. The gene analysis for Wilson's disease (ATP7B gene) was preoperatively carried out by the amplification refractory mutation system-PCR. Homozygous and heterozygous deletion of 2871 cytosine (C) were detected in the recipient and donor, respectively, in the ATP7B gene. Serum ceruloplasmin level was sufficient in the donor. The right hepatic lobe graft was transplanted to the recipient. Immediately after the liver transplantation, the copper metabolism improved to increase the serum ceruloplasmin levels up to the normal range, and decrease the urinary copper excretion. However, the serum ceruloplasmin levels gradually decreased below the normal base line, although the urine copper levels continued to be low without any clinical symptoms. We should perform gene analyses and confirm the serum ceruloplasmin levels in donors before living donor liver transplantation for Wilson's disease, to screen for their impairment of copper metabolism. After living donor liver transplantation for Wilson's disease, we should carefully follow-up the transition of serum ceruloplasmin levels in the recipient.