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A new energy method of describing crack growth rate is proposed. TheR-ratio is one of the main parameters which influence the experimental kinetic fatiguefracture diagrams da/dN - DK. The present-day methods of constructing kinetic fatiguefracture diagrams on the basis of energy dissipation in each loading cycle (related to ahysteresis loop area) make it possible to obtain a model invariable in relation to stressratio. In this paper, the comparison of these two methods, their faults and features, aswell as the results obtained for selected types of steel have been presented. For theexperimental verification, the results of fatigue crack propagation studies for 18G2Aand 40H steels have been utilized. In contradiction to the force factor Kmax, the energyparameter DH describes synonymously the fatigue crack propagation rate,independently on a stress ratio R. The linear dependence of crack propagation rateda/dN on energy dissipation of plastic deformation ahead of the crack tip for oneloading cycle has been discussed with taking into consideration the consequences forfitting models in double logarithmic axes.