A method for providing poria cocos extract of K2 with an increment. The method comprises the following steps:(a) mixing poria cocos with a solvent to provide a first mixture; (b) alkalifying the first mixture to obtain a second mixture; (c) acidizing the second mixture to obtain a third mixture; (d) alkalifying the third mixture to obtain a fourth mixture with a pH value greater than 7; and (e) neutralizing the fourth mixture, wherein K2 is at least one of tumulosic acid, dehydrotumulosic acid, polyporenic acid C, and 3-epi-dehydrotumulosic acid.