Silicon carbide base ceramic tubes were synthesized from blend polymers of polycarbosilane (PCS) and methylhydrogen silicon oil (H-oil) by polymer precursor method. This precursor method consisted of melt spinning, thermal oxidation curing and pyrolysis processes. Pore structure observed at cross sections of obtained tubes depended on H-oil content, melt-spinning temperature and oxidation curing conditions. At 578K for melt-spinning, however, a considerable amount of H-oil was decomposed during the spinning process. The resulting H-oil contents were usually lower than the starting H-oil contents. In the case of the 578K melt spinning, however, unique single pore structures were often observed in the tubes by adjusting the curing conditions. At 40% of the H-oil content, large pores with thin walls were observed at the cross-section, while such structures were difficult to be controlled. By reducing the melt-spinning temperature to 543K, the starting H-oil contents could be maintained during the spinning process. The cross sections of the tubes often showed multi pores in this case.