Al/Cu multilayered composite has been successfully synthesized by a new method of severe plastic deformation named accumulative roll bonding and folding (ARBF). The microstructure evolution, mechanical properties and interdiffusion of the multilayered Al/Cu composite were characterized. Fracture surfaces after tensile tests were examined by scanning electron microscopy (SEM). Sintering treatments at temperatures between 300 and 500 ? C were applied to the as-rolled laminates. As increasing the number of ARBF cycle, copper layers were necked and fractured. With increasing ARBF cycles, strength, microhardness and elongation of these composites increased. Observation revealed evidence of a mixture of failure mechanisms: cleavage, ductile failure, and intergranular fracture. The crystallite size of Al and Cu, which calculated using the Rietveld method, was 70nm for aluminum and 50nm for copper after 10 cycles of ARBF. By increasing the number of ARBF cycles, diffusion of Cu atoms was increased. Three different types of phase development were detected in the interface region. As the sintering time and/or temperature increased, the Cu 9 Al 4 phase became dominant.