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The strength behaviors of Fiber Reinforced Plastics (FRP) Composites can be greatlyinfluenced by the properties of constitutive materials, the laminate structures, and load conditions etc,accompanied by many uncertainty factors. So the reliability study on FRP is an important subject oflittle has been done on the roles played by fuzzy variables. In this paper, a fuzy reliability model forFRP laminates is established first, in which the loads are considered as random variables and the strengthsas fuzy variables. Then a numerical model is developed to ases the fuzzy reliability. The Monte Carlothe second part of this paper, a generalized fuzzy reliability model (GFRM) is proposed. By virtue of thefact that there may exist a series of states between the failure state and the function state, a fuzzyassumption for the structure state together with the probabilistic assumption for strength parameters isadopted to construct the GFRM of composite materials. By defining a generalized limit state function, the(FORM) applicable in calculating the reliability index. Several examples are worked out to show thevalidity of the models and the efficiency of the methods proposed in this paper. The parameter sensitivityanalysis shows that some of the mean values of the strength parameters have great influence on theand diferent fuzzy assumptions are also discussed. It is concluded that the GFRM is feasible to use, andcan provide an efective and synthetic method to evaluate the reliability of a system with diferent typesof uncertainty factors.