Abstract: Continuous fiber-reinforced nitride ceramic matrix composites are the main development direction of high-temperature wave-transparent materials, fiber is the pivotal issue which restrict the development of high-temperature wave-transparent composite materials, and SiBN ceramic fibers are a new kind of ceramic fibers which have excellent performances of high temperature resistance, wave transmission and mechanics. Polyborosilazane was used as ceramic precursor, and SiBN continuous fiber was used as reinforcement, SiBN fiber reinforced SiBN ceramic matrix composites were prepared by precursor infiltration-pyrolysis method. The thermal expansion properties, mechanical properties, fracture modes and microstructures of SiBN fiber reinforced SiBN ceramic matrix composites were investigated, and the preparation of new high-temperature wave-transparent ceramic matrix composites by precursor infiltration-pyrolysis was explored. The results show that the SiBN fiber reinforced SiBN ceramic matrix composites exhibits distinct brittle fracture characteristic, the bending strength and tensile strength of the composites are 88.52 MPa and 6.6 MPa respectively, which means the mechanical properties of the fiber still needs to be improved.