Abstract: The MoSi₂/Al₂O₃ ceramic composites were prepared by the reaction sintering process, in which the metal Mo, Si and Al powder as the raw material in order to effectively enhance the room temperature toughness and strength of MoSi/Al₂O₃ composite, and to reveal the resistivity with the purpose of sintering temperature variation. The samples' phase composition and microstructure, sintered at different temperatures, were investigated by SEM and XRD, and the mechanical properties and resistivity were investigated. The experimental results indicate that the MoSi₂/Al₂O₃ ceramic composite shows good performance in the argon protect atmosphere at 1 200℃. The apparent porosity is 20.7%, the volume density is 4.8 g/cm³, the fracture toughness value is 9.72 MPa·m^1/2, and the resistivity is 6.0×10^-2 Ω·cm. MoSi₂/Al₂O₃ composite structure is mainly formed by Al₂O₃ cladding and MoSi₂ continuous cladding phase composition. The organizational structure is symmetrical. When the sintering temperature is 1 200℃, MoSi₂ conductive phase connects each other to shape interconnected network distribution, and the cladding layer of Al₂O₃ coated MoSi₂ conductive phase become thinner, MoSi₂ phase can easy to break the Al₂O₃ cladding phase to communicate with each other, which is contribute to reduce the resistivity.