Objective：To study the effects of necrosis factor alpha（TNF-α） and interleukin 6（IL-6）on liver regeneration in grafts using a novel model of partial liver transplantation in rats. Methods：Rats subjected to 50% liver resection（control） were compared with rats that underwent total hepatectomy and 50% partial liver transplantation. Livers were preserved at 4℃ for 45 min and 10 h respectively. The expression of the proliferative cell nuclear antigen（PCNA），TNF-α and IL-6 of graft in rats were evaluated by immuno histochemical method 1，2，4 d after operation，respectively. The mRNA of TNF-α and IL-6 was detected by reversed transcript polymerase chain reaction（RT-PCR）. And the relationship of graft regeneration and those cytokines were investigated.Results：Prolonged time of cold ischemia（10 h） was associated with a dramatic decrease of PCNA（P < 0.05）. TNF-α and IL-6 was significantly decreased in recipient rats compared with liver resection and 45 minutes of cold preservation group（P < 0.05）. The peak of liver regeneration delayed 24 h postoperation compared with liver resection group. Conclusion：TNF-α and IL-6 are significantly associated with the regenerative activation of the partial liver transplantation in early stage. Prolonged cold ischemia decreases the liver regeneration by expression of TNF-α and IL-6 production in graft.