Abstract: The elastic properties of three-dimensional woven carbon fiber reinforced C-SiC binary matrix(3D woven C/C-SiC) composite were studied. Based on the scanning electron micrographs (SEM) of 3D woven C/C-SiC composite, the micro-structure was analyzed, a series of assumptions were proposed, and the micro-mechanical model was founded. The elastic properties of 3D woven C/C-SiC composite are evaluated with homogenization method. The variable regularity of elastic modulus is also studied as the warp angle increases. The results of the numerical calculation agree with the experiments very well, and the method of numerical calculation is proved to be accurate; as the warp angle increases, the elastic modulus in the warp direction decreases and the elastic moduli in other directions increase, but the in-plane shear modulus and the elastic modulus in thickness direction increase a little.