In the study the authors used a mechanical and a densitometric method for the determination of the strength properties of the stems of winter rape of the Jantar variety. They determined the dynamic shearing energy and the dynamic shearing energy per unit of stem cross section area, natural as well as after the removal of the parenchyma, and density and a number of parameters the function which was to permit the interpretation of X-ray images of the stems. A significant relationship was observed between the strength parameters obtained in the mechanical and the X-ray experiments. The simultaneous application of the mechanical and the X-ray methods for the study of the strength characteristics of stems considerably extended the scope of information concerning the strength properties of rape stems. Moreover, the study demonstrated the applicability of the densitometric method for the assessment of the strength properties of rape stems.