AIM: To explore the dynamical changes of histology, histochemistry, energy metabolism, liver microcirculation, liver function and posttransplant survival of liver graft in rats under different warm ischemia times (WIT) and predict the maximum limitation of liver graft to warm ischemia. METHODS: According to WIT, the rats were randomized into 7 groups, with WIT of 0, 10, 15, 20, 30, 45, 60min, respectively. The recovery changes of above-mentioned indices were observed or measured after liver transplantation. The graft survival and postoperative complications in each subgroup were analyzed. RESULTS: Liver graft injury was reversible and gradually resumed normal structure and unction after reperfusion when WIT was less than 30min. In terms of graft survival, there was no ignificant difference between subgroups within 30min WIT. When WIT was prolonged to 45min, the recipients' long-term survival was severely insulted, and both function and histological structure of liver graft developed irreversible damage when WIT was prolonged to 60min. CONCLUSION: The resent study indicates that rat liver graft can be safely subjected to warm ischemia within 30min. The levels of ATP, energy charge, activities of glycogen, enzyme-histochemistry of liver graft and its recovery potency after reperfusion may serve as the important criteria to evaluate the quality of liver graft.