The invention provides a method for improving stability of cyclohexanone ammoximation catalyst TS-1 molecular sieves. The method comprises the steps: mixing synthesized TS-1 molecular sieves with a 5% to 10% (mass concentration) carbon-precursor aqueous solution in accordance with that the mass/volume ratio is 1g: (10 to 50)ml, carrying out stirring for 4 to 12 hours at a temperature (room temperature to 50 DEG C), and carrying out centrifugal separation, so as to obtain molecular sieves; predrying the separated molecular sieves for 0.5 to 2 hours at the temperature of 80 DEG C to 100 DEG C, and then carrying out drying for 10 to 12 hours at the temperature of 120 DEG C to 140 DEG C; and roasting the dried molecular sieves for 1 to 4 hours at the temperature of 400 DEG C to 600 DEG C in an inert atmosphere. According to the method, the structural erosion to TS-1 caused by ammonia water can be effectively inhibited, the stability of the TS-1 in the ammonia water is improved, the loss of an active ingredient, i.e., titanium during reaction is lowered, the obtained catalyst shows excellent catalysis stability, and the conversion ratio of cyclohexanone and the selectivity of cyclohexanone-oxime still can respectively reach 100% and 90% after the catalyst is repeatedly recycled.