Radionuclide transfer from soil to pant (TF) is one of the key parameter for estimation of radiation exposure to organism. The success of their application depends on possibility of prediction and understanding of uptake processes. For this reasons the analysis of results of 238U and 220Ra uptake by different species of plants in site contaminated by radioactive wastes are presented. There was established that relations between transfer factor and radionuclide concentration in soil for all plants are approximated by power function TF = aCs-b. The relations between radionuclide concentrations in plants and soil in region of low soil radionuclide concentration are approximated by linear function. The range of radionuclide concentrations in soil with linear function depends on plant species.