PURPOSE: A corn flour containing a liquefaction enzyme and an enzyme stabilizer is incorporated with water and subjected to the liquefaction reaction under specific conditions, then filtered, thus extracting starch directly from corn with high industrial efficiency.

CONSTITUTION: After parts of low starch content as kernel and embryo buds are removed, the corn is crashed into flour of 30W100 mesh particle size and incorporated with 0.1W2w/w% of a purified liquefaction enzyme that is a heat-resistant amylase produced in a bacterium as Bacillus subtilis and free from protease and fat- decomposing enzyme, and 0.05W5w/w% of an enzyme stabilizer as calacium carbonate or sodium chloride. The are subjected to the liquefaction at a pH of 5W8 and 80W120°C under stirring for 5W90min to liquefy the starch in the corn and simultaneously coagulate the protein. Then, they are filtered and the starch is extracted.