Method for extracting soy isoflavone from bean pulp

The invention discloses a method for extracting soy isoflavone from bean pulp. The method comprises the steps of: firstly, extracting the soy isoflavone from the bean pulp by using alcohol, then extracting by using ethyl acetate and then purifying by using a silica gel chromatography column, wherein an eluting agent comprises chloroform and methanol in a volume ratio of 5:1, or chloroform and acetone in a volume ratio of 1:3 or ethyl acetate and methanol in a volume ratio of 7:1; and finally re-crystallizing to obtain the soy isoflavone. The method for extracting the soy isoflavone from the bean pulp can be used for obtaining the soy isoflavone with the purity of more than 60 percent rapidly without repeated re-crystallization, the process is simple and the separation cost is lowered.