To provide a solid surface material which is excellent massive in appearance, and looks like a stone by solidifying a mixture in which polymer particles are mixed in a resin matrix syrup to form a thick board, and cutting the thick board into sheets.

Polymer particles are preferably formed of a thermoplastic resin such as acrylic resin, and mixture thereof with polycarbonate. The resin is preferably treated or coated with a fixing agent or a coupling agent prior to the mixing with the resin matrix. By increasing the adhesivity of the particle surface to the resin matrix, generation of a gap, mixture or the like which generates cracks is eliminated between the particles and the resin matrix. The resin matrix preferably consists of materials of many different types. The resin matrix is preferably formed of the thermoplastic resin such as the acrylic resin, and a mixture thereof with a polycarbonate.