In this paper the whole body transference and retention dynamics of ,134,Cs by whole body counter were well described by a two-exponential function, that is: R(t)=18.04 e,-9.3157t,+45.13 e,-0.0473t,. There are two retention components, fast and slow. The effective and biological T,1/2, were 0.07 and 16.38 days respectively. Results indicated that after i. v. injection radionuclides ,134,Cs through 7 weeks observation, the retention data in skeleton could be fit well by an exponential expression: R(t)=0.0029 e,-0.121t,. Where the retention T,1/2, was only 5.73 d. While the retention data of ,134,Cs in testes also could be well described by an exponential equation: R(t)=0.0047 e,-0.133t,. Where the retention T,1/2, was also only 5.21 d. As a whole, the study showed that the dynamic retention of radioactivities of ,134,Cs in the whole body, skeleton and testes fall rapidly with the prolongation of observing time. So that the absorption dose in the whole body, skeleton and testes rose slowly.