The invention discloses a metal base material coated with a carbide coating and a preparing method of the metal base material. The preparing method includes the following steps that under the inert atmosphere or vacuum atmosphere, the metal base material is added into fluoride fused salt containing a permeating agent and in the molten state, and heat preservation reacting is carried out; and the permeating agent is one or more of simple substances or oxides of chromium, vanadium, niobium, titanium, silicon and zirconium. The preparing method is simple in process, free of strict limitation to processes like the material mixing sequence, and wide in applicability. The carbide coating prepared on the surface of the metal base material is compact, even and controllable in thickness, firm metallurgical bonding is formed between the coating and a base, the bonding force is high, the surface performance of the base material is improved, and excellent performance like high hardness, the high-wearing feature, occlusal force resistance, high-temperature oxidation resistance, environment corrosion resistance and the like are achieved; and the material surface performance is improved, the service life of hardware is prolonged, and the industrial application scope of the metal material is expanded.