Abstract: A mattress foundation comprised substantially entirely of wood and having a rectangular configuration defined by a pair of longitudinal side assemblies, a pair of transverse end assemblies and a longitudinal center board, wherein the support surface of the foundation is formed from a plurality of spaced transverse slats, some of which being wider at the center one-third portion of the foundation for enhanced strength. A plurality of braces extend inwardly from corner portions of the foundation to the center board to provide additional support strength.