VEHICLE DOOR GLASS ASSEMBLY AND METHOD FOR REGULATING POSITION OF DOOR GLASS

A vehicle door glass assembly capable of regulating a position of a door glass may include a door frame forming a vehicle door; a garnish joined to a periphery of the door frame to finish an outer side face of the door frame; the door glass installed so as to be raised or lowered within the door frame; a glass run assembled to the door frame to support a periphery of the door glass; and a slider installed in an inner side face of the door glass to guide a raising or lowering movement of the door glass, where the garnish is provided with a restraint device configured to prevent the slider from moving in a longitudinal direction of a vehicle.