The stiffness matrix of the suspension, which enters into the system of differential equations of motion for the frame of a vibrosieve employed in the field of drilling, is presented. A method is described for determination of the stiffness matrix. Results of experimental investigations are tabulated. A comparative evaluation of stiffness matrixes is performed for a physical model of a vibrosieve, and also an SV1LM vibrosieve, and vibrosieves produced by the Baroid and Swaco Companies.