PURPOSE: To develop a clad material made of a high strength superplastic Al alloy excellent in corrosion resistance by cladding the core material made of an Al-Zn-Mg-Cu alloy having a specified compsn. with the surface material of an Al-Zn alloy under specified temp. conditions.

CONSTITUTION: The ingot of the Al alloy contg., as essential components, by weight, 3 to 8% Zn, 1 to 3% Mg and 1 to 3% Cu and furthermore contg. one or ≥ two kinds among 0.05 to 1.0% Mn, 0.05 to 0.5% Cr, 0.05 to 0.5% Zr and <0.10% Ti is subjected to homogenizing heat treatment at 400 to 550°C and is thereafter subjected to hot rolling into the lamellar core material having ≤25μm grain size, and the sheet material of the Al-Zn alloy contg., as essential components, 0.8 to 1.3% Zn is formed into the surface material, and they are formed into a clad material in which the cladding ratio is regulated to 2 to 4% per single face, which is subjected to hot cladding rolling at 300 to 500°C into the clad material. This clad material is subjected to annealing by holding under heating of two stages at 350 to 550°C, is cooled at ≥100°C/hr cooling rate, is thereafter subjected to cold rolling of at least ≥50% and is heated to 400 to 550°C at ≥500°C/hr temp. raising rate.