Objective To investigate the memory amelioration of the AD model rat after a single or combined transplantation of the neural stem cells(NSCs) modified with gene of NGF or GDNF. Methods The AD model rat was made by cutting unilaterally the fibria\|fornix of male SD rat.Eight to ten days after surgery,the genetically modified and unmodified NSCs were implanted into the lateral cerebral ventricle of the rats.Two weeks after transplantation,the amelioration of memory impairment of the rats were detected by Morris water maze. Results The average escape latencies of the last three blocks in NGF and NGF+GDNF groups were lesser,and the percentages of swim distance in the platform quadrant were greater than that in NSC group( P