The invention discloses a traditional Chinese and western medicine combination prescription for treating enteritis and a preparation method. The Chinese and western medicine combination prescription includes traditional Chinese medicine components and western medicine components, wherein the traditional Chinese medicine components comprise bighead atractylodes rhizome, astragalus membranaceus, radix codonopsis, poria cocos, coix seed, tangerine peel and antler gelatin, and the western medicine components comprise metronidazole, levofloxacin, domperidone, cisapride, sulfasalazine and norfloxacin. The preparation method includes the following steps of: step one, raw material selection; step two, raw material pretreatment; step three, preparation of the traditional Chinese medicine components; step four, preparation of the western medicine components, step 5, mixing of the traditional Chinese medicine components and the western medicine components and step 6, packaging and storage. The preparation method uses a combined process of traditional Chinese medicines and western medicines, shortcomings of the traditional Chinese medicines and shortcomings of western medicines are mutually complemented, the antler gelatin is used to reduce the side effects of some drugs, such as nausea, vomiting and bloating, moreover, the addition of tangerine peel can be used for regulating the middle warmer, stomach qi rising, nausea and vomiting can be treated, safety and reliability are achieved, the cure rate is high, relapse is not prone to occurring, adverse reactions do not exist, and both symptoms and root causes are addressed.