Abstract:SiC has favorable physical and mechanical properties and it has become an important material for the large aperture substrates of space mirrors due to its excellent synthetical performance. The technologies of fabrication, manufacturing and surface modification of SiC mirrors have acted a more and more important role in the application of space optical systems. Combined with the engineering application, the characteristics of the SiC material in common use for space mirrors are analyzed and four kinds of fabricating methods are introduced. The current status of the application and the surface modifications of SiC mirrors at home and abroad are researched and the guide lines and the technics for the surface modification coatings are discussed in detail. According to the internal current status of engineering application, it isconsidered that developing high performance SiC substrate materials in a high speed and using the large aperture PVD equipment to prepare high quality SiC coatings for the surface modifications are the development direction in the future.