A plastic molding mold for inmold labelling including an inner surface defining a cavity and adhering a label placed prior to molding on the inner surface to an outer surface of an article to be molded simultaneously with molding. The mold having a label support portion protruded from the inner surface and having a surface slightly projected into the cavity, and an exhaust port opened in the side of the label support portion. The exhaust port is connected to an air suction device provided outside, and air stayed between an article to be molded and a label is removed as the air suction device is actuated.