The invention relates to a machining technology of U-shaped pieces, in particular to a binaural U-shaped piece welding-free integrated finish machining method for a thermonuclear fusion reactor. The binaural U-shaped piece welding-free integrated finish machining method comprises the steps of manufacturing U-shaped blank pieces by using a forming die; carrying out first ultrasonic flaw detection on the U-shaped blank pieces after rough machining is carried out on the U-shaped blank pieces; carrying out rough machining again after heat treatment is carried out, then carrying out second ultrasonic flaw detection, picking out qualified U-shaped pieces, and carrying out a performance test by extracting samples from bodies; machining the U-shaped pieces which are qualified in the performance test into U-shaped pieces with allowance, and then manufacturing the U-shaped pieces into primary semi-finish machining U-shaped pieces by carrying out first artificial aging treatment on the U-shaped pieces; machining the primary semi-finish machining U-shaped pieces into U-shaped pieces with allowance, and then manufacturing the U-shaped pieces into secondary semi-finish machining U-shaped pieces by carrying out second artificial aging treatment on the U-shaped pieces; machining the secondary semi-finish machining U-shaped pieces into finish machining U-shaped pieces, drilling through holes in the end surfaces of side plates of the finish machining U-shaped pieces, and obtaining finished U-shaped pieces through WEDM (Wire Electrical Discharge Machining) after a metal wire is enabled to penetrate through the through holes. The binaural U-shaped piece welding-free integrated finish machining method disclosed by the invention has the advantages that the machining efficiency is high, and the product quality is good.