Abstract: A water mattress construction for a water bed having a foam assembly forming a cavity for surrounding and supporting a water-filled bladder. The foam assembly is formed of several layers of foam having different densities to provide strong support for the water bladder and prevent bulging. There are layers of low-density foam on the top and bottom of the foam assembly and a center core or frame of a medium density enclosing the cavity and bladder installed therein. The entire foam structure and bladder retain their shape by being bound on the sides and bottom by a high-strength, non-stretchable, non-woven fabric bonded securely to the foam assembly. The foam and bladder assembly is then covered with a low-density foam having a high recovery factor. The entire structure is then covered with a heavy-duty material and ticking which is quilted and has the appearance of a conventional mattress.