In ancient China, a doctor was an official position. The doctor was originally an ancient official position. Since the Zhou Dynasty, in the vassal states, there were three levels of officials below the king: ministers, doctors and scholars. Each level is divided into upper, middle and lower levels, such as Shangqing, Zhongqing and Xia Qing. After the Sui and Tang Dynasties, doctors became a title rather than an official position. Similar to the current title. For example, Dr. Jianyi and Dr. Guanglu are the same title. Because during the reign of Song Huizong in Song Dynasty, the official rank was redefined, and the establishment of medical officers also increased. The highest rank of medical officer is doctor, which is equivalent to the current Minister of Health. The doctor is a doctor, that is, the deputy ministerial level. Since then, it has become a practice to turn regular doctors into doctors and call those irregular doctors doctors doctors, which has continued to this day.