Abstract: A dyeing method for a substrate material and the colored substrate material thereby produced comprises the steps of laying a substrate film made of melted TPU on a surface of a substrate material (a fabric or a non-fabric), cooling the film, coloring the film with a water soluble dyes free of solvents, washing extra dyes off the film, and drying the substrate material. Because of the covalent bond between TPU and the water soluble dyes, the adhesion of the dyes is greatly enhanced. Since the steps of laying substrate films and coloring are independent, small amounts of coloring pieces can be done without raising production cost too much. Further, since the water soluble dyes do not contain solvents, the product thereby produced is free from pollutant emission, which is environmentally friendly.