A process for producing dried powdery soybean, in which dried powdery soybean containing substantially none of components other than those of soybean, being resistant to oxidation and excelling in storability can be obtained in relatively short time. Dried powdery soybean can be produced through a process comprising: adding water and tocopherol to water-washed soybeans and effecting immersion thereof for a given period of time (immersing step), and steaming the immersed soybeans together with immersion water (steaming step); crushing the steamed soybeans into grains of given size (crushing step), and adding pectinase enzyme and tocopherol to the crushed soybeans and water and agitating the thus obtained mixture solution at a temperature at which the pectinase enzyme is active for a given period of time (enzyme treating step); and rapidly heating the mixture solution after the enzyme treatment to thereby deactivate the enzyme (deactivating step), rapidly cooling the deactivated mixture solution, screening the cooled mixture solution so as to carry out micropulverization of solid contents of the mixture solution into individual cell level, separation and slurry formation (separating step), and drying the slurry by spray drying (drying step).
