SiBZrOC ceramics were obtained using the sol-gel process through the chemical reactions of hybrid alkoxysilanes with boric acid and Zr(OnPr)4. Si-O-Zr and Si-O-B bonds were both detected in the precursor and ceramics. XRD patterns indicate that the presence of B promotes the crystallization of ZrO2 and the formation of zircon. Raman spectra showed the highly graphitized free carbon at 1600°C with very small I(D)/I(G) ratio. Turbostratic graphite with 10-20 layers graphene was clearly observed in TEM, confirming the significant promoting effect of B on the graphitization of free carbon, which was probably due to the partial substitution of C with B atoms in graphite layer.