The present invention discloses a oxidation and coloring technology of watch hairsprings that includes: Step 1, washing: washing the hairspring in detergent and cooking in the mixed solution of oleic acid and ammonia; Step 2, oxidation and coloring: placing the washed hairsprings in the quartz tube, putting into the heat treatment furnace and treating for 2-12 minutes at 380DEG C-450DEG C in the air medium to form a colorized oxide layer of 20-200nm thin on the hairspring surface; Step 3, curing: treating the hairspring at 180-200DEG C for 5-6 hours in the medium of nitrogen or oxygen in the curing oven to cure the oxide layer. There are some advantages as follows: the hairspring is passivated during oxidation and coloring and completes torsional moment drift in a short time; the hairspring presents yellow, red, blue or black color to increase the additional value.