The present invention discloses a gear machining and heat treatment process, and the gear machining process successively comprises forging, normalizing, quenching and tempering, vertical machining, gear shaping, annealing, vertical machining, gear shaping, vertical milling, stabilizing aging, gear grinding, nitriding and finished product inspection, wherein the step of normalizing is normalizing at (880 +/-10) DEG C for (3-4) h, and then cooling in air; the step of quenching and tempering is quenching and tempering at (850 +/-10) DEG C for (3-4) h, quenching with water, and cooling with oil; the step of the annealing is annealing at (530 +/-10) DEG C for (3-4) h, cooling in a furnace in the heating and cooling rate of less than or equal to 50 DEG C / h; the step of stabilizing aging is stabilizing aging at (510 +/-10) DEG C for (3-4) h, and cooling in the furnace in the heating and cooling rate of less than or equal to 2 5 DEG C / h; and the step of nitriding is nitriding at (510 +/-10) DEG C for (10-12) h, and cooling in the furnace in the heating and cooling rate of less than or equal to 2 5 DEG C / h. The gear machining and heat treatment process is more reasonable, and can reduce distortion after nitriding to improve the overall performance of a gear.