This paper introduced a new method for fabricating aluminum foam sandwich (AFS) panel with large scale dimension. The foamable Al-based precursor was prepared by optimized FORMGRIP foaming method which was developed from melting process. The blowing agent was specially modified to increase the decomposition temperature. To avoid surface oxidation, the mild cover sheets were aluminized by cold spraying technique. An optimized hot pressing technique was designed and showed great advantages in the bonding of the precursor to the cover sheets at low temperature. The precursor and the cover sheet was successfully bonded by using a specially designed hot pressing apparatus via diffusion bonding. It is shown that the pre-bonding in the three-layer composite is beneficial to the formation of metallurgical bonding surface in AFS. The foaming and bonding process was carried out simultaneously. This approach for manufacturing AFS may have particularly importance on applying the AFS panels to industrial applications.