The invention discloses an oral medicine for preventing and treating leukocytopenia caused by chemotherapy, which is prepared from the following traditional Chinese medicines in parts by weight: 2-3 parts of herba epimedii, 1-2 parts of psoralea, 2-3 parts of astragalus root, 1-2 parts of sun-dried ginseng, 1-2 parts of bighead atractylodes rhizome, 2-3 parts of poria cocos, 1- 2 parts of prepared licorice, 1-2 parts of angelica, 1-2 parts of chuanxiong rhizome, 1-2 parts of red peony root, 1-2 parts of prepared rehmannia root, 1-2 parts of donkey-hide gelatin, 2-3 parts of spatholobus stem, -3 parts of rhizoma polygonati, 1-2 parts of chickens gizzard-membrane, 1-2 parts of fried malt, 1-1.5 parts of pinellia tuber and 1-1.5 parts of dried orange peel. The donkey-hide gelatin can be replaced by 0.5-1 part of antler glue. The oral medicine provided by the invention is a decoction, or can be prepared into an oral liquid, granules, a fluid extract or pill according to traditional methods. The oral medicine provided by the invention can be used for preventing and treating leukocytopenia caused by chemotherapy and can also be used for preventing and treating leukocytopenia caused by various other factors.