The authors submit their initial experience with the use of bone cement with methotrexate in the treatment of primary and secondary malignities of bones. As a basis they use the analogy of using bone cement with gentamycin the molecular structure of which is similar to that of methtrexate. In the experimental part of the work in vitro evidence was provided of methotrexate stability when exposed to heat or oxidation; and the kinetics of its release from pores of bone cement were revealed. In experimental dogs the effect of cement with methotrexate on neighbouring bone was investigated in the early period in the immediate vicinity necrosis of the trabeculae was found, during the late period healing processes. The clinical use of bone cement with methotrexate was started in 1986. In 17 surviving patients only in one case local progression of a tumour in the vicinity of cement with methotrexate was found. The aim of the work is to find a possible local treatment of bone malignities, in particular metastatic ones, which will be not only an emergency solution but will extend our therapeutic possibilities.