Disease coding is based on the international classification of diseases, based on certain characteristics of the disease, according to certain rules of disease classification and coding method to express. At present, the classification of diseases is generally used is icd classification method, is the world health organization formulated the international unified classification of diseases, it is mainly according to the cause of disease pathology, clinical manifestations and anatomical location and other characteristics of the disease, the disease will be divided into categories, become an orderly combination, and with the coding of the way to express. The coding of diseases is to facilitate the management of disease cases, as well as to facilitate the query as well as the integrated classification in medicine. It makes the name of the disease standardized and formatted, which is the basis for the application of medical information technology, hospital information management and other clinical information systems. At the same time, the coding of diseases is conducive to the classification of diseases, which is one of the important bases for the control of medical expenses, as well as the basis for the medical and administrative management of hospitals.