This is a multi-center, open-enrollment, retrospective, non-interventional epidemiologic study without any clinical treatment. Its primary objective is to understand 1) incidence of drug-induced liver injury, including incidences among all the hospitalized patient, among patients in department of hepatic diseases, digestive diseases, oncology, hematology etc., individually; 2) epidemiologic characteristics of drug-induced liver injury, including suspected medications, clinical types, histological characteristics, severity and outcomes.