The colored films formed on 304 stainless steel plates by immersion treatment and electrochemical one in a solution containing sulphuric acids and chromic acids were studied by SEM, AES, and spectrophotometer. The thicknesses of the films by 20 minutes treatment were about 200 nm and it became thinner as the treatment times were increased. The surface texture showed a tortuous network of interlinking pathways. The color of the 304 steel surface changed from metallic white to gray, black, red, yellow-green, and green-blue, gradually, by the treatment time was increased. The reflectivity measured by UV-VIS-NIR spectrophotometer was reduced from max. 38% of basis metal to min. 3.5% of colored surface.