Abstract: According to the characteristic of low-cycle fatigue, theequation of S-N curve of concrete is simplified. A new model ofstrength degradation and the predictor method of life period for concrete underlow-cycle fatigue loading are proposed, and the necessary parameters areobtained by the fatigue test. By comparison with the evolution of theactual strain and the Miner rule, the model and method are shown to reflect thedamage of low-cycle fatigue of concrete correctly.