A carbon-coated transition metal nanocomposite material includes carbon-coated transition metal particles having a core-shell structure. The shell layer of the core-shell structure is a graphitized carbon layer doped with oxygen and/or nitrogen, and the core of the core-shell structure is a transition metal nanoparticle. The nanocomposite material has a structure rich in mesopores, is an adsorption/catalyst material with excellent performance, can be used for catalyzing various hydrogenation reduction reactions, or used as a catalytic-oxidation catalyst useful for the treatment of volatile organic compounds in industrial exhaust gases.