In this study,the cytogenetic cross-adaptive to ionzing radiation and Cadmium were explored,by using embryo cells of mice. The results shwoed that 1,2,4 and 8cGy ,60,Co γ-rays could reduce the frequenecy of chromosome aberration in embryo cells of mice in vivo caused by subsequent Cd 4mg/kg body weight; By contrast,0.25,0.5,1.0 and 2.0mg/kg Cd could reduce the frequency of chromosome aberration in embryo cells of mice in vivo caused by subsequent 1.5cGy ,60,Co γ-rays. The time effects of 0.5mg/kg Cd to 1.5Gy ,60,Co γ-rays on the cross-adaptive response in embryo cells of mice were obsreved. The time interval 0. 5 h, the cross-resistance no significant p,>,0.05, the time interval 4h,p,<,0.05,8h,p,<,0.01, but time interval 12h and 24h, no cross-resistance were obserced,instead of coopration. All these results indicat that the ionizing radiation and cadmium each other could induce cross-adaptive response and have time effect.