Abstract: The pure copper/pure aluminum and pure copper/aluminum alloy were used for 400 ℃warm rolling and annealing heat treatment, and the interface binding strength test, interface metallophase microstructure analysis and interface SEM analysis were also performed for the resulting Cu/Al cladding materials. The results show that, the formation of the Cu/Al mesophase at the Cu/Al cladding materials interface requires a certain gestation period, and the formation process is:nucleation→nucleation growth→continuous growth along the interface laterally→vertical direction along the normal direction of the interface growth. The best annealing process of pure copper/pure aluminum cladding materials is 300 ℃×1 h, and the maximum interface bonding strength can reach 2.4 N/mm. While the pure copper/aluminum alloy is 300 ℃×3 h, the maximum interface bonding strength is 3.1 N/mm, which ensures the formability of the materials and prevents the formation of intermetallic compounds. The pure copper/pure aluminum alloy is more likely to form a brittle intermetallic compound phase than the pure copper/pure aluminum cladding material interface, which can lead to the decrease of the interface bonding strength and the brittle fracture of the interface under peeling conditions.