In order to prepare silicon carbide(SiC) fiber tubes, polycarbosilane precursor(PCS) fibers were irradiated by 10 MeV electron beams(EB) under atmosphere. The effects of irradiation art, heat treatment temperature,and absorbed dose on the performance of SiC fiber tube have been discussed and the relevant mechanism was studiedusing IR spectra. The results show that the best irradiation technique is using irradiation time of 20s with an intervalof 5 min, and the best heat treatment temperature is 350°C. IR spectra analysis shows that the Si−H and Si−CH,3, react with oxygen induced into irradiated PCS to form the structures of Si−OH and C=O. And the bridge structures of Si−O−Si and Si−C−Si have been produced when the irradiated PCS fibers are treated in suitable temperatures. The SiC fiber tubes could be obtained from the precursor fibers with an absorbed dose of 2.0−3.5 MGy and treated by furanidine, and the thickness of the ceramic tube is dependent on the absorbed dose.In order to prepare silicon carbide(SiC) fiber tubes, polycarbosilane precursor(PCS) fibers were irradiated by 10 MeV electron beams(EB) under atmosphere. The effects of irradiation art, heat treatment temperature,and absorbed dose on the performance of SiC fiber tube have been discussed and the relevant mechanism was studiedusing IR spectra. The results show that the best irradiation technique is using irradiation time of 20s with an intervalof 5 min, and the best heat treatment temperature is 350°C. IR spectra analysis shows that the Si−H and Si−CH,3, react with oxygen induced into irradiated PCS to form the structures of Si−OH and C=O. And the bridge structures of Si−O−Si and Si−C−Si have been produced when the irradiated PCS fibers are treated in suitable temperatures. The SiC fiber tubes could be obtained from the precursor fibers with an absorbed dose of 2.0−3.5 MGy and treated by furanidine, and the thickness of the ceramic tube is dependent on the absorbed dose.