Ex situ partial liver resection was performed in 2 patients with hepatocellular carcinoma (HCC) with Child A-liver cirrhosis that was untreatable by conventional liver resection techniques. In both cases, an extended left lobectomy was first performed, and then the autologous lateral segment was transplanted after removing segment 4 (or + a part of segment 5, 8) together with the tumor by the bench procedure. Although there might have been no difference in preoperative liver function in these cases, the postoperative course was quite different. The first case was successful with an uneventful postoperative course, but, the second case went into postoperative liver failure and the patient died of multiple organ failure on the 20th postoperative day. The cause of liver failure in the second case might be attributable to: 1) prolongation of cold preservation time for the bench procedure (196 min); or 2) over reduction of the native remnant liver (right lobe) due to resection of the huge tumor. In conclusion, the technique using ex situ partial liver resection and transplantation of the remnant section of the liver might be a useful method to extend surgical treatment for some cases of HCC untreatable by conventional liver resection. However, the indications should be carefully considered in each case, since graft damage can occur rapidly during the bench procedure due to combined liver cirrhosis.