SiC coated C/SiC and C/SiBCN composites were prepared by chemical vapor deposition (CVD) combined with polymer infiltration and pyrolysis (PIP) techniques. The effects of thermal cycling on bending properties of these composites were studied. Compared with SiC-C/SiC, the average bending strength of SiC-C/SiBCN was measured as around 605 MPa at room temperature, which increased by 126.6 %. After the oxidation at 1000 °C and 1200 °C for 3 cycles, the residual bending strength of SiC-C/SiBCN was separately measured as 417 and 342 MPa. The corresponding strength retention rates at 1000 °C and 1200 °C were 68.9 % and 56.5 %, respectively. Compared to the SiC ceramic matrix by PIP, the porosity of SiBCN ceramic matrix was lower. Meanwhile, SiO2 and B2O3 were formed during the oxidation of SiBCN, which could decrease permeation ration of the oxygen. Thus, the oxidation resistance and strength retention rate of SiC-C/SiBCN were significantly better than SiC-C/SiC composite.