Abstract: In order to study the physical and chemical properties of quick- cooking black beans and compare the difference with the raw material,the nutritional content,amino acid composition and in vitro digestibility of black beans were analyzed,while the physicochemical properties of black beans were investigated by the methods of scanning electron microscopy,fourier transform infrared spectroscopy and differential scanning calorimetry.The results showed that compared to the raw black beans,the starch content of quick- cooking black beans was increased by 9.13%,and contents of crude protein,crude fat and total amino acid were slightly reduced,while the protein solubility was decreased and in vitro digestion was increased,based on the analysis results of the nutrition,amino acid composition and in vitro digestion.The microstructures of raw black bean and quick- cooking black bean powder were observed by using scanning electron microscope.The particles of the quick- cooking black soya bean were aggregated and blocked and its protein solubility was deteriorated.The result of fourier infrared spectrum scanning showed that composition of quick- cooking black bean changed little and the protein aggregated to decrease its solubility.Through DSC analysis,it showed that the protein of quick- cooking black bean denatured completely after processed since there was no endothermic peak appeared in the thermal analysis.