The fatigue hysteresis behavior in fiber-reinforced ceramic–matrix composites under multiple loading stress levels has been investigated. Based on the fatigue damage mechanism of fiber slipping relative to matrix in the interface debonded region upon unloading/reloading, the fatigue hysteresis loops models corresponding to different interface slip cases under multiple loading stress levels have been derived. The fatigue hysteresis loss energy and interface slip corresponding to single/multiple loading stress levels and different loading sequences have been investigated. The fatigue hysteresis loops of unidirectional SiC/CAS–II composite under multiple loading stress levels have been predicted.