1. A printing relief plate having convexities formed on a surface of a plate material, the convexities being adapted to print halftone dots on a print medium by transferring ink to the print medium, wherein: on the surface of the plate material, there are provided a solid area, an image forming region in which the convexities are formed in plurality, and at least one detecting portion for determining a magnitude of a printing pressure applied to the printing relief plate in a case where ink is transferred to the print medium from the printing relief plate; the convexities and the detecting portion are positioned lower than the solid area; and it can be determined whether the printing pressure is an appropriate printing pressure or not by comparing a density of at least one detecting portion image, which is printed on the print medium by transferring ink to the print medium from the detecting portion, with a density of a solid area image, which is printed on the print medium by transferring ink to the print medium from the solid area.