Abstract: In this paper,the acoustic emission(AE) technique is successfully applied to meassura the glass fiber fragment length distributions in Single——Fiber——Composite(SFC) test.The interfacial shear strength is determined by developing a statistical modal using a Weibull model for fiber strength.A.comparison is performed to the results of the statistical model and the model of D.Jaques and J.P.Favre,which shows that the statistical model is quite raasonable in determining the intermining the interfacial shearstrength.