In order to improve the oxidation resistance and thermal shock resistance properties of the TaSi₂-MoSi₂ borosilicate glass coating for porous SiCO ceramic heat insulation composite, TaSi₂-MoSi₂ borosilicate glass coating on the surface of SiCO ceramic composites was prepared by brush-air sintering method. The microstructure and phase compositions of the coatings with the content of borosilicate glass respectively of 23%,31%,38%,41% were comparative observed by XRD and SEM with EDS. The thermal cycle experiment of the coated samples was performed by heating for 5 min at 1 500℃,then taking out to cool naturally down to room temperature.The result shows that the TaSi₂-MoSi₂ borosilicate glass coating with the content of borosilicate glass of 38% has fewest holes and cracks,the mass loss of the coating is -2.1%. It can be concluded that the TaSi₂-MoSi2 glass coating with the content of borosilicate glass is 38% has the best oxidation resistance and thermal shock properties.