Objective To establish the oxygen glucose deprivation (OGD)/reoxygenation experimental model of hippocatnpal neurons of rat in vitro, and to try to identify the length of time for producing optimum injury in this model. Method The primary hippocampal neurons of newborn Sprague-Dawley rats were cultured for 7 days and randomly (random number) divided into a control group and OGD groups. The OGD groups were assigned into 1 h, 2 h, 4 h, 6h, 8 h and 10 h subgroups in accordance with different lengths of time for oxygen glucose deprivation. The neurons of OGD groups were placed into a tri-gas incubator containing 0.5% oxygen and the culture medium was substituted with the glucose-free Earle' s balanced salt solution, simulating cerebral ischemia injury in vivo. The morphology of neurons was observed after reoxygenation for 24 hours. The MIT assay was used to determine the rate of survived cells derived from the value of optical density (OD) of cells. The lactate dehydro-genase (LDH) content in culture medium was detected to evaluate the neuron injury. The apoptotic rate of neurons was measured by using flow cytometry. Dunnett-test and Spearman correlation analysis were used to analyze the data with SPSS version 16.0 soft ware package. Results The morphological damage of neurons in OGD groups aggravated gradually, optical density and cell survival rate decreased (rs= -0.961 and rs = -0.966, P <0.01), and the amount of LDH increased (rs = 0.990, P <0.01) with longer duration of exposure to oxygen glucose deprivation, and the rate of neuron apoptosis increased obviously which was significantly statistical difference in com-parison with the control group (P < 0.05). Under the setting of oxygen glucose deprivation for 6 hours, the apop-tosis rate of neurons approximated to 50% . Conclusions The oxygen glucose deprivation/reoxygenation model of rat's hippocampal neurons in vitro was established successfully. From the findings of morphological changes and apoptosis rate of neurons, the oxygen glucose deprivation for 6 hours may be the suitable length of time for inducing neuron injury in this model.