Abstract: A sleeper sofa mattress includes a foam body with an opening for the receipt of a spring assembly. The spring assembly is positioned in the foam body so as to rest between hinge lines that allow the mattress to be folded into the sleeper sofa. A support substrate is attached to the foam body and spring assembly. The support substrate in the form of a high tensile strength polypropylene mesh serves to positively hold the foam body and mattress together and spread the load thereby reducing wear and increasing the comfort and overall service life of the mattress. Insulator pads are also provided across the spring assembly and a cushioning member across the top of the entire mattress completes the combination.