The braided longitudinal tensile test of anti-oxidation coating coated non-trimming and trimming 3D four directional carbon/carbon (C/C) composites were investigated.The strength,elastic modulus and stress-strain curves were obtained in atmospheric environment at room temperature,800 and 900 ℃. The fatigue life data and residual stiffness with cyclic loading were obtained from the braided longitudinal tensile/tensile fatigue test for two kinds of specimens when temperature raised to 800℃. The static tensile and fatigue specimen fractures were observed by scaning electron microscope ( SEM ) . Tensile failed mechanism and tensile/tensile fatigue failed mechanism were analyzed. Results showed that the tensile strength became higher with temperature increase,and the mechanical property of non-trimming specimens was much better than that of trimming ones. The residual stiffness of 3D four directional C/C composites first increased and then decreased. The main failed mode of specimen was fiber tensile, but bundles of fibers pulled out when temperature elevated.More pull-out fiber in fatigue failed than tensile failed at the same temperature,and the matrix was delaminated obviously under fatigue load.