Abstract: Cordierite bonded SiC composite materials were in-situ synthesized by using silicon carbide particles as aggregate, with talc powder, clay and α-Al₂O₃ powder as matrix materials, and introducing appropriate Al₂O₃-SiO₂ ceramic fiber. The effect of fiber addition on properties of the composite material was studied. The results show that the composite material was mainly composed of SiC and cordierite. With the Al₂O₃-SiO₂ ceramic fiber mass fraction of 8%, the fiber combined with the matrix closely and distributed well. With the increase of fiber addition, the flexural strength of the composite material first increased then decreased, while the thermal shock resistance increased. When the fiber mass fraction was 8%, the composite material reached the largest flexural strength of 33 MPa and had relatively good comprehensive properties.