SiC coating grows in the flexible carbon foam via chemical vapor deposition (CVI) to investigate the effect of CVI-SiC on mechanical properties and thermal insulation performance of reinforced foam. The microstructure morphology and phase composition of the carbon foam and the reinforce foams are analyzed by SEM and XRD, respectively. The pore structure and thermal conductivity of the carbon foam and the reinforce foams are measured by mercury intrusion porosimetry and heat flow tester, respectively. The compression strength of the reinforce foams is measured by universal tester. The results show that the β-SiC coating grows uniformly on the carbon foam surface and the surface morphology of SiC coating depends on the surface morphology of matrix. When the thickness of SiC coating increases, pore size in the 3D interconnected network structure decreases, and the porosity decreases from 99.68% to 58.39%; the compression feature of reinforced foams changes from elastic deformation to plastic deformation, and the compression strength increases from 0.02 MPa to 3.14 MPa; the heat transfer area increases,and the thermal conductivity of foam samples increases from 0.026 W/(m·K) to 0.101 W/(m·K).