PURPOSE: To develop a roll bonded panel having excellent strength and corrosion resistance, by using a clad plate consisting of an Al alloy as a core material and an Al plate as a facing material and a pure Al plate in constituting said panel.

CONSTITUTION: A pure Al facing material 3 is clad at 5W20% ratio on an Al alloy core material 2 contg. 3.4W4.5 Zn and 0.2W0.5% Mg to form a clad material 4. A press-sticking preventive agent is printed on the surface of such material 4 to a prescribed shape, and a pure Al plate 5 having high corrosion resistance is superposed thereon and the laminated materials are hot and rold rolled to a final plate thickness. The three-layered clad plate is annealed for 20min at 400°C and is allowed to stand for 40min to cause the age hardening of the material 2 of the clad material 4. The plate is then put into dies and a fluid pressure is introduced to the non-press-stuck part coated with the press-sticking preventive agent to bluge only the plate 5, whereby a roll bonded panel 1 bulged on one side is produced.