To find the differential chemical indicators between the raw and milk-processed corals, which can provide references for improving the quality standards of the milk-processed corals. A serial of the milk-processed corals was prepared by the orthogonal design of the processing factors, including the milk-to-water ratio, the decocting temperature, the drying time and the drying temperature. Calcium carbonates content and crystal form in the raw and milk-processed corals were tested by titrimetric analysis and X-ray diffraction, respectively. The organic and inorganic compositions of the raw and milk-processed corals were characterized by infrared spectroscopy.The mass concentration of calcium carbonatewas about 80% in the raw and milk-processed corals, while the calcium carbonate content could increase slightly when the raw coral was processed according to the processing specification. The crystal form of calcium carbonatewas calcite in the raw and milk-processed corals, while the X-ray diffraction peak of the raw coral at 2θ=47.953° could change after the processing. The organic compositions were quite different between the raw and milk-processed corals. The characteristic bands in the regions of 3 050~2 750, 1 770~1 720 and 1 710~1 600 cm-1 (corresponding to fats, proteins, carbohydrates, etc.) in the infrared spectra of the milk-processed corals were significantly stronger than those in the infrared spectrum of the raw coral. The areas of these infrared spectral bands were also sensitive to the variations of the processing factors, including the milk-to-water ratio, the decocting temperature, the drying time and the drying temperature. Infrared spectroscopy can objectively and quantitatively discriminate the raw and milk-processed corals. It was also possible to use infrared spectroscopy to evaluate the compliance of the processing methods of the milk-processed corals.