The utility model relates to a special fitting for a rock drift hydraulic drill rig, particularly a special fine drill for a hydraulic drill rig and the special fine drill for a hydraulic drill rig can punch bolt holes of which the diameter is 32 mm. The utility model is composed of a drill rod and a drill head, wherein the drill head is connected with the drill rod; the drill rod is a hollow hexagonal steel rod body, the tail part is connected with a connecting sleeve of a shank of the hydraulic drill rig, and the front part is connected with the drill head; the drill head is in a cast tooth shape. Compared with an air drill, the speed of the utility model for punching the bolt holes is raised by 3 times and personnel are saved by 2 times. After the hydraulic drill rig is provided with the special fine drill, the hydraulic drill rig can be used for drilling blastholes in three light blasting and the construction progress can be enhanced. In addition, the utility model has the advantages of simple structure and convenient operation.