The clinical data of 100 cases of patients clinically diagnosed with drug-induced liver injury at present, the Chinese herbal medicine category accounted for 24%, which is the top of various types of drugs causing liver injury. Lin Aijin [2] synthesized nine reports on drug-related hepatitis published in China from 1998 to 2002, and the liver damage caused by Chinese herbal medicines accounted for 30.00% to 74.14%, and there is a trend of increasing year by year. (1) The chemical composition and pharmacological activity of herbs are very complex, and many plants possess a set of defense system to protect themselves by synthesizing chemicals such as alkaloids and periodic peptides that have toxic effects on the animals that eat these plants. These chemicals may act directly on biochemical targets, be available for therapeutic use in a range of doses, or may cause cell death. The liver acts as a chemical processing plant, performing its role of scavenging and metabolizing lipophilic endogenous and exogenous chemicals, with the potential for exposure to reactive intermediate metabolites that could lead to injury. (2) Traditionally considered “non-toxic” Chinese herbal medicines are found to be hepatotoxic in modern clinical practice, such as Huang Yao Zi, Tian Tian Tian Ye, He Shou Wu, etc. (3) There are many cases of herbal medicines with the same name or different names, which can lead to poisoning due to misidentification and misuse. For example, Fangqi has a wide Fangqi, powder Fangqi and other differences, wide Fangqi clinical reports have liver and kidney toxicity. (4) drugs due to the origin, planting, harvesting season, processing, transportation and storage conditions, can also affect its efficacy and adverse reactions, such as taking large doses of unconstituted raw shouwu will lead to liver damage. (5) herbal medicine causes the hepatotoxic damage also with the dosage form, the dose, the combination and the use method and so on, such as the traditional Chinese medicine gardenia conventional dose is 3 ~ 9g, if take 30g or even higher dose, may lead to the liver damage. Second, the organism factor: (1) because the patient self, misuse or superstition some toxic herbal medicine, Chinese medicine or secret recipe, partial prescription; or because the doctor or the patient lacks to some herbal medicine preparation has the potential hepatotoxic understanding, thus taking herbal medicine dose is too big, or use the medicine for too long and cause liver damage. (2) Depending on the age or health condition, such as the elderly, children, infirmity, maternity and liver and kidney dysfunction, are more likely to cause toxic reactions. (3) Toxic reactions can occur in a few people at regular doses due to individual differences; some people have hereditary liver metabolism defects, which can easily lead to drug-related liver damage; the body’s idiosyncratic (idosycracy) and allergic reactions to herbs or their metabolites, i.e., damage to the liver through immune-mediated mechanisms. In addition, since there are few studies on the pharmacokinetics of herbs, especially compounded herbs, for technical reasons, we do not know what effect the administration of an herb may have on the activity of the metabolizing enzymes of the drug in question, which may lead to the accumulation or metabolic transformation of other drugs taken with it in the body, thus producing toxic effects on the liver.