Objective　To explore expression change of LC3B in hippocampus, and the hippocampal neuronal death after global cerebral ischemia/reperfusion in rats.　Methods　Transient global cerebral ischemia was induced by four-vessel occlusion method. The SD rats weighing 250~320 g were randomly divided into 2 groups: the sham-operated group and the ischemia/reperfusion group. The expression of LC3B was detected by immunohistochemistry analysis.　Results　The expression of LC3B in the ischemia/reperfusion group got increased after 2h of reperfusion, and the peak appeared at 12 h of reperfusion.　Conclusions　The occurred LC3B activation leads to the neuronal death of hippocampal CA1 induced by ischemia/reperfusion. The earlier high expression of LC3B occurred, the more severe neuronal death appeared after 20-min global cerebral ischemia. These results suggest that autophagy pathway play a more harmful role in neuron death after long time ischemia.