The invention relates to a method for extracting organic acid from a fermenting liquid. The method comprises the following processes: first, producing the organic acid through fermenting to obtain an organic acid-containing coarse liquid with the pH of 1 to 5; second, extracting the organic acid from the organic acid-containing coarse liquid which is obtained by the first process by using an ester compound-containing extracting medium, and obtaining the organic acid-containing extracting liquid, wherein the ester compound is a diester compound with the carbon number of 10 to 30; the diester compound is dialkyl ester of aliphatic dicarboxylic acid. Through the combination of the ester compound and the alkylamine compound, the organic acid can be obtained selectively and effectively. Namely, the organic acid can be selectively obtained through a simple operation without extracting the component (particularly, glucose) from the fermenting liquid nearly.