The molybdenum coating was successfully deposited on the surface of silicon carbide by the magnetron sputtering method and the crystallized heat treatment process, and its surface morphology and chemical composition were analyzed. The SiC_p/Cu composite was prepared by vacuum hot-pressing sintering, and the effects of the interfacial layer thickness on the thermal conductivity property were studied in detail. Results are as follows: molybdenum coating can be successfully deposited on the surface of silicon carbide by magnetron sputtering method, the roughness and the thickness of the film are enhanced with the sputter time postponed, and the molybdenum on the surface is in amorphous state. After the crystallized heat treatment, the molybdenum coating is in densification crystalline state. The sputtering time affects the thickness of the Mo coating and the thermal conductivity of SiC_p/Cu obviously. With the time postponed, the thickness of the Mo coating is increased. And the thermal conductivity increases firstly and then decreases as the sputtering time increases. The thermal conductivity of the SiC_p/Cu composite in 800 ℃crystallized heat treatment fabricated by the 9 h Mo coated SiC powders in 850 ℃ hot pressing can reach 274.056 W/(m·K) when the volume fraction of SiC is about 50%.