The invention discloses a short-process forging method for a nuclear power main pipe billet channel. The short-process forging method reduces forging difficulty and forging heating number and comprises the steps as follows: A, selecting steel ingots and removing damage of the steel ingots; B, pressing a plier handle and rolling; C, upsetting, swaging and octagonally forging; D, rolling, distributing and swaging; and E, locally upsetting a flange at a pipe mouth, and discharging a finished product. With the adoption of the method, the main pipe mouth part is subjected to local covering and local upsetting for forming, the forging difficulty and the forging heating number are reduced, the forging cost is reduced, and the forging efficiency is improved; meanwhile, the forge piece surface cracking is prevented from aspects of steel ingot surface quality, plier handle and end surface transition fillet, end surface inclination, forge piece water gap reservation, small rolling reduction forming, flame damage removing after forging and the like; and with the adoption of small rolling reduction forming, the forge piece surface quality is improved.