Polyfunctional carbosilane(P.F.C.S.) was prepared by alcoholysis from the low molecular carbosilane and multifunctional hydrosilane(H.S.) was prepared by hydrolysis from methyldichlorosilane in alkaline condition as the stabilizer for polycarbosilane filament (P.C.S.F.). The P.C.S.F. was coated(3% weight increase) by dipping in P.F.C.A.(A-P.C.S.F.) and H.S(H-P.C.S.F.) solution, respectively and heated at 15$0^{circ}C$ for 30 minutes under the nitrogen(or argon) gas atmosphere to crosslink the stabilizer. The another one was prepared by heating in air(O-P.S.S.F.) without treating of stabilizer. The silicone carbide fiber(Si.C.F.) was prepared by pyrolyzing the stabilizer coated P.C.S.F. at 10-3 torr in electronic furnace with raising the temperature in the rate of 10$0^{circ}C$.min to 150$0^{circ}C$ and the chemical structure was deduced by IR spectrum of gas generated. The residual oxygen in the final products, Si, C.F. by elemental analysis were 0.12, 0.16, and 0.32 mole based on the empirical formula for A-P.C.S.F, H-P.C.S.F., and O-P.C.S.F., respectively.