"Jeong Dan Whan(征丹丸)" is a Chinesε patent medicine, which is used for acute and chronic indigestion, dyspepsia, vomiting in Korea. This medicine consist of 14 kinds of powdered crude drugs. For the identification of individual ingredients in such powdery mixtures, microscopic method may advantageously be used as it requires only a small amount of specimens. In this paper, the effectiveness of this method is exemplified by the identification of the ingredients in "Jeong Dan Whan" which contains 14 powder crude drug ingredients.