Abstract: C/SiC composites were prepared by hot pressing sintering using SiC powder and carbon fiber as raw materials. The effects of sintering pressure, sintering temperature and carbon fiber content on the bulk density and bending strength of C/SiC composites were analyzed by orthogonal experiment and single factor tests. The results show that the influence of carbon fiber content on the bulk density of composites was the greatest, followed by sintering temperature and sintering pressure, and the influence of sintering temperature on bending strength was the greatest, followed by carbon fiber content and hot pressing pressure. When the sintering pressure was 25 MPa,the carbon fiber volume fraction was 30% and the sintering temperature was 2 100℃, the composites exhibited the excellent comprehensive properties with the bulk density of 2.30 g·cm^-3 and the bending strength of 80.50 MPa. The change of sintering process and carbon fiber content affected the properties of the composites by affecting the sintering degree of SiC and the interface bonding strength of carbon fiber to SiC matrix.