Groups of ,Stylonychia mytilus, were exposed to ,60,Co γ−rays for 1.5h and irradiated to 100, 300, 500, 800, 1200 and 1500Gy, respectively. On the fifth day after the irradiation, surviving fractions of the irradiated groups were about 47%、18%、16%、8%、5% and 3%, respectively, with the increasing the doses. . Based on the observation, radioprotection of fullerenols to ,Stylonychia mytilus, groups exposed to ,60,Co γ−rays was studied. The results showed that the surviving fractions of the ,Stylonychia mytilus, in fullerenols solutions increased significantly in either the high dose groups and the low dose groups, in comparison to the control group. It was also found that the radioprotection was related to concentration of the fullerenols. The study indicated that fullerenols, as a potential radioprotection medicine, could scavenge free radical and reduce damage of the cells from γ−ray radiation.