Objective To observe the effect of curcumin on behavior,blood brain barrier(BBB)and ex-pression of glial fibrillary acidic protein(GFAP)and cyclic nucleotide 3′phosphohydrolase(CNPase)in hippocam-pus of radiation injured brain(RIB)rats. Methods SD rats were divided into radiation group,treatment group and negative control group. RIB rats model were established by X ray,and rats in treatment group were treated by curcumin. Morris water maze test were taken to study learning memory of rats in each group. The expression of Ev-ans blue(EB)in brain tissue and the expression of GFAP and CNPase in hippocampus were detected to observe the effect of curcumin on the BBB of RIB rats. Results In RIB rats,learning memory were decreased significant-ly,permeability of BBB were increased. GFAP expression in brain tissue was increased,and CNPase was de-creased(P < 0.05). After the treatment of curcumin,learning memory of rats were improved,the permeability of BBB was decreased,GFAP was decreased,and CNPase expression was increased(P < 0.05). Conclusion Cur-cumin can significantly reduce the damage of BBB in RIB rats,decrease the expression of GFAP and increase the expression of CNPase in hippocampal,which indicate that curcumin has curative effect on radiation injured brain.