To provide a polyurethane adhesive having a high adhesion strength and a preparation process of a decorative sheet coating material having a curved or uneven surface using this adhesive.

A polyurethane adhesive comprises a main agent obtained by adding a vinyl chloride/vinyl acetate/vinyl alcohol terpolymer resin or a vinyl chloride/vinyl alcohol copolymer resin to a thermoplastic polyester urethane resin and dissolving this mixture into a solvent, and a polyisocyanate hardener. In a preparation process of a decorative sheet coating material, the polyurethane adhesive is applied onto the rear side of a decorative sheet and dried, and the sheet is applied to a core material having a curved or uneven surface and bonded to it.