To provide a lightweight layered body for mattress having a simple structure, shape-retention property and flexibility, and a mattress using the same.

A layered body to be housed in a housing cover consists of a first sheet-like foam body 2 having vent holes and shape retention property and second soft, net-like foam bodies 4, 6, 8 and 10 arranged on at least one face of the first foam body and having meshes having a mean size smaller than that of the vent holes in the first foam body 2. The first and the second foam bodies are composed of first and second foam thread-like bodies 2a, 4a, 6a, 8a, and 10a 2b, 4b, 6b, 8b and 10b obliquely crossing each other with the intersections being welded together. The first foam body 2 and the second foam bodies 4, 6, 8 and 10 are laminated with their diamond-shaped meshes 3, 5, 7, 9 and 11 oriented in the same direction. The foam bodies are made of a polyethylene resin foam with the expansion ratio of 15 to 80, and include closed cells and/or open cells. The first foam body may be a sheet-like foam body of a closed cell structure having vent holes and an uneven surface.