Micro drilling and reaming tool

The utility model relates to the technical field of machining, in particular to a micro drilling and reaming tool which comprises a tool handle and a tool bit, and the tool bit comprises a tool bit body, a main drill tip, a chamfering angle and a rough drilling step. The main drill tip is arranged in the center of one end of the tool bit body; a chamfering angle is arranged at the edge of the main drill tip; the rough drilling step is arranged on the outer edge of the tool bit body. On one hand, by arranging the main drill tip and the chamfering angle, the main drill tip and the chamfering angle participate in cutting at the same time during drilling, so that under the condition of the same contact stress, due to the large contact area, the stress on the unit area of the drill bit is small, and the cutting area of the drill tip can be effectively increased; further, the drilling efficiency of the cutter can be greatly improved, and the hole machining precision can be improved; and on the other hand, the rough