A novel carborane-POSS pre-polymer has been synthesized and characterized as precursor for ceramic andapplied on the surface treatment of carbon fiber by precursor infiltration and pyrolysis (PIP) method. The ceramizationtransformation process was investigated by using TGA, DSC, Py-GC/MS, etc. Ceramic yield after heating up to 1000 oC innitrogen was 74.3 % and the produced ceramics exhibit excellent thermal and thermo-oxidative stability. Mechanicalmeasurement revealed that the coated carbon fiber maintained 81.22 % of its original tensile strength, and was stable underhigh temperature in flowing air up to 600 oC.