Sandwich panels for high temperature applications were fabricated using superplastic diffusion bonding of aluminum foam core. Superplastic 5083 aluminum alloy sheets and closed-cell aluminum foam ALPORAS were used as skins and a core. Compressive stress of 0.35 MPa at 823 K for 10 min in vacuum resulted in the penetration of the cell wall into the superplastically-deformed skin, and thus solid state diffusion bonding was achieved. EDS measurement confirmed the diffusion of magnesium from the 5083 alloy to the ALPORAS foam regions. The bonding strength measured by vertical tensile tests at room temperature was 32% of the original ALPORAS foam.