Abstract: This study investigates the effects of high temperature and oxidation on the static strength and cyclic deformation behavior of braided SiC fiber-reinforced ceramic matrix composites (CMCs). Uniaxial tensile and cyclic loading-unloading mechanical property tests were conducted on CMCs at room temperature and in a high-temperature environment of 1100℃. The tensile behavior of the material exhibits a bilinear characteristic under both room temperature and high-temperature conditions, with an additional nonlinearity occurring specifically at room temperature. High temperature results in a decrease in the tensile strength and stiffness of the material but also leads to the homogenization of the internal material texture, yielding more uniform mechanical properties. Scanning electron microscopy characterization of the fracture morphology of failed specimens revealed that, at high temperatures, oxidation of the interface layer reduces the bonding strength between fibers and the matrix, resulting in an increased fiber pull-out length. During cyclic loading-unloading, damage between fibers and the matrix in the composite material intensified significantly, characterized by increased fiber pull-out length, irregular fiber fracture morphology, discontinuous crack propagation along the fiber axis, multiple fiber damages, and increased gaps between the interface layer and fibers. Energy-dispersive spectroscopy analysis of the oxidation characteristics showed that a high-temperature environment accelerates the oxidation reaction of the material, with oxidation phenomena primarily occurring at the interface layer.