Column experiments have been carried out on the migration of 60Co and 137Cs through a sandy soil layer in order to examine the migration of radionuclides controlled by several different migration mechanisms. Radionuclide concentration distribution between the effluent and the sandy soil layer was measured after 10 L of the solution containing the radionuclides were introduced into the column from the top of the layer at a constant flow rate. Most of the 60Co and 137Cs remained attached to the layer, and a small amount of each radionuclide; at concentrations of 0.3 and 0.1%, respectively; flowed out from the soil layer. The migration of the mobile fraction of these radionuclides is different from that expected of an ideal cation. These results suggest that the mobile fraction of these radionuclides migrates as non-cationic forms which are not adsorbed into the soil matrix by equilibrium ion exchange.