The invention discloses a ternary composite silicon carbide fireproof material. The material comprises a base material and a binding agent, the base material comprises 30-40 wt% of silicon carbide aggregate, 10-55 wt% of silicate mineral, 5-35 wt% of industrial-grade aluminous raw material and 10-35 wt% of cordierite, and the use amount of the binding agent is 6-12 wt% of the base material. In addition, the invention further discloses a preparation method of the ternary composite silicon carbide fireproof material. According to the method, through an in-situ synthesis mode, a high-strength andlow-expansion mullite-cordierite matrix is introduced to silicon carbide aggregate particles and used as a binding phase, the problem is effectively solved that it is difficult to evenly mix and bindartificially-synthesized powder and aggregate in the prior art, the technical defects of low strength, poor thermal shock resistance and the like caused by the problem are overcome, and the quality of the silicon carbide fireproof material is remarkably improved. According to the ternary composite silicon carbide fireproof material, the technology is easy, the firing temperature is reduced, the manufacturing cost is greatly lowered, the material has the wide market prospect, and the material helps to promote improvement and application development of industrial technologies.