Abstract: Three kinds of thick-wall needled C/C composites, namely IR-C/C, IP-C/C, P-C/C respectively, were prepared by means of chemical vapor infiltration(CVI)and resin impregnation/carbonization(PIC), CVI and pitch impregnation/high pressure carbonization (HPIC), HPIC.The thermodynamic property and density uniformity were studied. The results indicated that, axial tensile strength of IP-C/C is 24.7 MPa, axial compressive strength of IR-C/C reaches to 200 MPa, while axial tensile strength of P-C/C is merely 7.4 MPa, which is 53% less than IR-C/C, and 70% less than IP-C/C. Material prepared by compound technology has lower thermal expansion coefficient, while the thermal expansion coefficient at 1000℃ of P-C/C is 3.566×10^-6℃^-1, which is 2.5 times than IP-C/C. IP-C/C and P-C/C are both prepared by high pressure carbonization, their densities are higher, density distribution are uniform, which make it own higher thermal conductivity coefficient.The density drop is 14.5% within the IR-C/C, and showing high-low-high distribution across the wall.The needled C/C composites, made by the technology of CVI+HPIC, has the excellent comprehensive performance and uniform distribution across the wall, all of these make it suitable for preparing the thick-wall composites.