Provided is a process for producing a porous aluminum object having a large surface area. The process for producing a porous aluminum object according to the present invention comprises: a step in which an aluminum alloy is cast and solidified to produce an aluminum alloy cast object having a solidified structure that comprises an alpha-Al phase 11 and a second phase 12, which has been continuously formed so as to intermingle with the alpha-Al phase; and a step in which the aluminum alloy cast object as a precursor is brought into contact with an extractant for dissolving away the second phase, thereby dissolving away the second phase 12 of the solidified structure within the precursor and producing a porous aluminum object that has a large number of pores extending inward from the surface.