Aiming at the problem of low bonding strength or warping which is prone to occur during the rolling process of large thickness steel/aluminum composite plate, the rolling composite technology of large thickness steel/aluminum composite plate based on prefabricated aluminum layer was proposed. Then, with the help of large thickness ratio rolling and advantage of easy bonding characteristic of aluminum-aluminum interface, the continuous high-strength rolling of large thickness steel/aluminum composite plate was realized. Taking Q235 steel and 1050 aluminum as substrates, the steel/aluminum composite plate with a thickness of 34 mm at a total reduction rate of 22.7% was prepared by two prefabricated aluminum layer processes, namely cold rolling prefabrication and non-isothermal prefabrication. The analysis of the shear strength of interface and the microstructure for the composite plate shows that the steel/aluminum composite plate with a shear strength of interface exceeding 74 MPa can be prepared by both prefabricated aluminum layer processes, and the interfacial microstructures are refined, and the bonding strength of interface for the composite plate exceeds the strength of the aluminum matrix. The shear fracture is located in the aluminum matrix and presents a ductile fracture. The oxide film formed by the heating of 1050 aluminum will break and disperse during the rolling process, without affecting the bonding strength of interface for the composite plate.