Aim To investigate the protective effects of beraprost sodium on cerebral cortical neuron injury in chronic aluminum-overload rats and its effects on PGIS-IP signaling pathway. Methods 75 SD rats were randomized into five groups: normal control group, chronic aluminum-overload group ( model group) and beraprost sodium groups-low dose (6 μg· kg-1 ), medium dose ( 12 μg · kg-1 ) and high dose (24 μg·kg-1). Aluminum gluconate (Al3+ 200 mg ·kg-1 d-1, once a day, 5d a week, for 20 weeks, p. o. ) was administered to rats of cerebral damage model. The rats of experimental groups were concomi-tantly treated with beraprost sodium ( p. o. ) daily for 20 weeks. After the model was built successfully, the spatial learning and memory( SLM) function was done by Morris water maze. The cortical neurons damage was detected by HE staining, SOD activities and MDA contents. The 6-k-PGF1α levels in cortex were meas-ured by ELISA. The expressions of PGIS, IP mRNA and IP protein were also studied. Results Compared with the rats of normal control group, the SLM function was significantly impaired ( P<0. 01 ) and considera-ble karyopycnosis was observed in model group rats. The SOD activities were weakened ( P <0. 01 ), the MDA contents increased ( P<0. 05 ) and the levels of 6-k-PGF1α raised significantly ( P <0. 01). The ex-pressions of PGIS and IP mRNA in the rats cortex obvi-ously increased ( P<0. 01 ), so did the expression of IP protein(P<0. 05). Compared with the rats of mod-el group, the SLM function of rats in experimental groups decreased significantly ( P<0. 01 ) and damage of cortical neurons reduced remarkably. The SOD ac-tivities increased ( P <0. 01 ) and the MDA contents decreased ( P <0. 01). Besides, the content of 6-k-PGF1α, the expressions of PGIS mRNA and IP protein in the rats cortex decreased significantly ( P<0. 05 ) as well as IP mRNA ( P<0. 01). Conclusion Our re-sults demonstrate that in cerebral cortical neuron of chronic aluminum-overload rats, beraprost sodium has notably protective effects and the mechanism might be related to PGIS-IP signaling pathway.