The hysteresis loop obtained in the course of low cycle fatigue test is to be the most important key to conjecture the process which is going on in the material. However, the information which the hysteresis loop possesses has hardly been utilized, except hysteresis energy in the case of hysteresis energy accumulation criterion for failure. In the present paper, the author proposed a rheological model that the material consists of elements with linear strain hardening properties. By using the model, the author interpreted stress-strain relation, or hysteresis loop, analysed hysteresis energy, and discussed hysteresis energy accumulation criterion in terms of effective hysteresis energy.