Carbon nanotube plays an important role in various applications due to its extreme optic, electronic and mechanical properties. In the present work, attempts have made to investigate the effects of incorporation of multiwall carbon nanotubes (MWNTs) on microstructure and mechanical properties of SiC composites. Firstly, carbon nanotubes were modified by chemical method in order to add carboxyl group on their surface. Then modified carbon nanotubes were located on the surface on SiC particles by silicon coupling agent. A designed carbon nanotube reinforced composite was obtained after pressureless sintering. SEM was employed to investigate the micro-structure of as-prepared SiC material. Its properties of, such as density, hardness, strength, etc. were determined in detail. The relationship between the micro-structure and properties of carbon nanotube reinforced SiC composite were discussed.