The invention discloses a machining method for a thread full-tooth block and relates to a block machining method. The problem of low precision of a thread full-tooth block is solved. The machining method comprises the main steps of 1, shearing of a rectangular workblank by a plate shearing machine; 2, leveling of thickness planes, 3, flat grinding and coarse grinding of the thickness planes, 4, milling of four right angle faces, 5, chamfering and drilling, 6, heat treatment, 7, flat grinding and accurate grinding of the two thickness planes, 8, blueing treatment, and 9, coarse and accurate cutting of all outlines on a linear cutting machine. The machining method is mainly used for tooth profile precision detection of a sawtooth thread.