The invention relates to the field of machining, in particular to an improvement of a boring cutter head. A fine-adjustment center water discharging eccentric boring cutter comprises a blind rivet, a cutter handle and a boring head body which are installed in sequence. The center water discharging eccentric boring cutter further comprises a blade seat and an eccentric block. A through hole is formed in the center of the boring head body, the eccentric block is installed in the through hole of the boring head body, the hole diameter of the boring head body is slightly larger than the diameter of the eccentric block, and the eccentric block and the boring head body are connected together through a fine-adjustment mechanism and a fastening screw. The blade seat is installed on one side of the eccentric block. According to the fine-adjustment center water discharging eccentric boring cutter, the eccentric block is designed, an installation angle is adjusted through the eccentric block and the blade seat, a cutter rod is effectively prevented from touching a small boss in the machining process, and an inner hole and the outer cylindrical face of the small boss can be machined; by means of the design of the hole, cooling liquid can directly reach the cutting part through a channel in the cutter in the machining process; meanwhile, a balance block is designed, too large vibration is avoided, feeding can be finely adjusted, and operation is greatly facilitated; by means of the design of a threaded plug, machining of the hole is facilitated, and cooling liquid is prevented from flowing out.