A nanocrystalline material based on a stainless steel surface. In percentage by weight, the nanocrystalline material comprises: 0 to 3% of carbon, 20% to 35% of oxygen, 40% to 53% of chromium, 10% to 35% of ferrum, 0 to 4% of molybdenum, 1% to 4% of nickel, 0 to 2.5% of silicon, 0 to 2% of calcium, and the balance of impurity elements. Also disclosed is a preparation method for the nanocrystalline material, and the nanocrystalline material that is based on a stainless steel surface and that is prepared by using the preparation method.