In this article, the influence of curing processing on the final ceramic yield of a highly branched polycarbosilane is discussed. Effect of pyrolysis conditions on the ceramic residue is also investigated. The results show that post-treatment can highly increase the crosslinking degree and pyrolysis yield, but has little influence on the final ceramic yield. The heating rate between 170 and 200 A degrees C shows a little effect on the ceramic residue. Adding the catalyst into polymer, pyrolysizing with the gas pressure and improving the heating rate during the pyrolysis process can efficiently increase the final ceramic yield.