DND in the gerbil hippocampus was performed by bilateral occlusion of carotid arteries for 20 min followed by reperfusion 2 or 7 days. The contents of Ca~(2+) and MDA in drosal hippocampus were measured after two days reperfusion. Neuronal density in CA1 sector of hippocampus was used as an parameter. Effects of nimodipine and Superoxide dismutase (SOD) on DND in hippocampus were observed after 7 days reperfusion.The results indicated that the levels of Ca~(2+) and MDA were increased significantly. DND in hippocampal CA1 sector was ameliorated by both nimodipine and SOD significantly. It was suggested that Ca~(2+) and Iipid peroxidation play an important role in the development of DND hippocampus after transient forebrain ischemia in gerbils. Calcium Antagonist and free radical scavenger have obvious protective effects on DND in hippocampus.