The invention discloses a medicine for curing liver and kidney cyst. The medicine is characterized by comprising, by dry weight, 30-40 parts of fruit of sweetgum, 30-40 parts of sargentg loryvine stem, 30-40 parts of dandelion, 30-40 parts of the fruit of Chinese wolfberry, 30-40 parts of the root of membranous milk vetch, 30-40 parts of poria cocos, 20-30 parts of plantain seed, 20-30 parts of common knotgrass Herb, 10-20 parts of the rhizome of oriental water plantain, 10-20 parts of corydalis tuber and 10-20 parts of the root of red-rooted salvia. The preparation method includes soaking all the Chinese herbs by three times, mixing extracts which are respectively obtained by soaking, concentrating the extracts, drying the extracts under the temperature not higher than 60 DEG C to obtain powder so as to produce powder, tablet or capsule medicine. The required dosage is not higher than 8 g for patients each time; to mild patients, liver and kidney cyst can be cured by taking the medicine for 15 to 30 days, and to severe patients, for 30 to 60 days.