Copper clad aluminum composite is a kind of bimetallic composite material, which has the characteristics of excellent electrical conductivity of copper and low cost and light weight of aluminum. With the continuous progress of material preparation and processing technology, copper-clad aluminum composite materials have gradually developed in the direction of high performance and structural function integration, and have become one of the key basic materials for lightweight, performance improvement, cost reduction and efficiency improvement in new energy power generation, electrical equipment and other fields. In the field of power, the busbar made of copper-clad aluminum composite material can effectively solve the problem of high caloric value and high loss of medium and low voltage switchgear. In this paper, the development status of copper-clad aluminum is reviewed, including applied material system, preparation technology, copper-clad aluminum interface bonding mechanism and strengthening mechanism, research status and future application prospect.