Abstract: The microstructure, physicochemical quality and molecular structure of four varieties of potato flakes were studied by scanning electron microscopy, physicochemical analysis and two-dimensional correlation spectroscopy aiming to screening special potato cultivars for processing.The results showed that the starch granule structure of four varieties of potato flakes were destroyed in different degrees owing to the production process of drying and crushing.The iodine blue value, solubility, swelling, freeze-thaw stability and retrogradation of four varieties of potato flakes were significantly different ( p < 0.05) . The infrared spectra of four varieties of potato flakes were similar on the whole.So the infrared spectra in the range of 1500~700 cm^-1 were selected to perform second derivative infrared spectroscopy. The obvious differences in positions, shapes and absorption intensities of peaks of second derivative infrared spectroscopy were observed in the wave number of 1200, 1300, 1330 cm^-1.Two dimensional synchronous correlation spectra showed that the intensity of automatic peak at 1650 cm^-1 were obviously different, this could be used for the identification of four varieties of potato flakes.