The present invention relates to a method for manufacturing a multi-hardness/multi-elasticity foam mattress by a continuous foaming process and a foam mattress manufactured by the same. The method andthe foam mattress are characterized in that a foam mattress is molded from different types of polyurethane foam, which have different levels of hardness and different levels of elasticity, by a continuous foaming process such that a plurality of foam unit blocks, which have different levels of hardness and different levels of elasticity, are formed integrally along the longitudinal direction of the foam mattress. The present invention is advantageous in that the foam mattress manufacturing method is simple and thus has a high productivity; the foam mattress has excellent durability and implements optimal body pressure distribution and body shape retaining effects; accordingly, the same can lower the electromyogram and improve the blood flow; the same helps maintain deep sleep, secure muscle flexibility, and maintain an ideal skeleton shape; and foam unit blocks in zones positioned on parts, which are symmetric about a foam unit block positioned at the center portion along the longitudinal direction of the foam mattress, have the same hardness and the same elasticity such that the foam mattress can be turned around and used.