PURPOSE: To improve substantially the workability in forming a pattern on a plastic molded item, by using a flexible spatula to stuff a colorant into grooves on the surface of the plastic molded item.

CONSTITUTION: In molding a base 2 of a plastic molded item, a grooves 5 having a pattern such as the grain of wood are formed. A colorant 6 for forming a pattern is applied on the surface of the base 2. Then the flexible spatula 9 having a rubber plate 7 attached to a grip 8 is engaged with part of the surface of the base 2 adjacent to the applied colorant 6, and is slid along the surface of the base 2 to spread the colorant 6 along the spatula 9. In this case, part other than the grooves 5 is not applied with the colorant, while the colorant 6 can be stuffed into the grooves 5 by the rubber plate 7. Thus, only the grooves 5 are deeply colored to form a clear pattern. Thereafter, a transparent protective film 10 is formed on the pattern.