Abstract: Damage analysis of axial tension specimen was implemented by stochastic progressive failure analysis and acoustic emission (AE) monitoring.The results show that the stochastic progressive failure analysis characteres failure of composite materials well. In the early load stage, the stochastic character of composite failure is apparent, and the failure occurs in the whole specimen. With the load increasing, damage accumulates, "stochastical critical nuclei" emerges and the composite fails completely and quickly.Once there is failure happens, fiber breakage number is positive correlative with AE events.The effect of matrix crack and interface debonding on the composites was also compared and it is found that interface debonding affects tensile strength drop of the composite more severely than matrix crack, if matrix crack and interface debonding are not taken into consideration, clustering characteristics of fiber fracture appears and the composite fails in brittle manner.