The pathway by which 60Co and 137Cs got into Area, and the type of uptake in animal were studied.The results showed that 60Co was taken up by gill and was transferred quickly to other organs through blood.There are more uptake pathways for 137Cs.The uptake of 60Co by Arca was mainly active transfer and the energy comes mainly from the process of biotic oxidation.On the contrary, the uptake of 137Cs by Arca was mainly a passive transfer, and for most organs the exchange through body-wall was a significant factor.