A door glass run attaches to a door frame of a vehicle for guiding upward and downward movement of a glass window. In the door glass run of this invention, a plurality of grooves formed in the bottom surface of the door glass run extend lengthwise and are spaced widthwise from each other at predetermined intervals. According to one embodiment, the grooves are arranged so as to successively increase in cross-sectional areas thereof from a centermost groove or centermost grooves to outermost grooves. According to another embodiment, the bottom surface of the door glass run includes both a central surface portion that is flat and free of grooves and side surface portions, which are formed on opposite side walls of the flat central surface portion and have grooves formed therein.