The newly derived relationship between the closure traction and the crack opening displacement by the modified shear-lag model is used to investigate the tensile failure behaviors of unidirectional fiber reinforced ceramics. The critical stress for matrix cracking and the critical stress to fracture the fiber are calculated for various crack configurations. Then, the failure of composite initiates as the applied stress exceeds the smaller of the matrix cracking stress and the fiber fracture stress. The differences of results between the present analysis and Marshall and Cox are discussed. Finally, the possible tensile failure modes and the transition conditions between different failure modes are summarized in this paper.