To simplify forming process of cladding materials with high performance, such as copper cladding aluminum composite materials, and to improve the interface quality of cladding materials, a novel forming process called Core-Filling continuous Casting (CFC) for bimetal composite materials is proposed. A conceptual equipment is developed, and the forming of composite bars of copper cladding aluminum is investigated. The basic technique theory of CFC, the reaction and bonded state of interface and the interfacial bonding strength of the cladding materials, as well as the influences of technological parameters are analyzed. The composite bars of copper cladding aluminum with 24mm in diameter of core material and 8mm in thickness of cladding layer are successfully fabricated. The results show that: (i) the proposed CFC process is feasible in principle; (ii) the composite bars of copper cladding aluminum having metallurgical bonding interfaces can be fabricated by CFC process under the conditions of liquid copper temperature of 1250~1300°C, liquid aluminum temperature of about 700°C and drawing velocity of 12~24mm/min; (iii) the copper layer thickness distribution is uniform both in the directions of portrait and circumference and (iv) the interfacial bonding strength is higher than that of core aluminum.