The three provinces refer to the three central institutions of the central government: Zhongshu Province, Menxia Province and Shangshu Province. Zhongshu province inherited the emperor's orders and drafted letters; After being examined and refuted by the provincial government, it was submitted to the emperor for approval; Shangshu province is responsible for implementing the imperial edicts and various government decrees approved by the emperor. The chiefs of the three provinces collectively served as prime ministers, and the three provinces had clear division of powers, each with its own division of labor and mutual constraints.
Shangshu province consists of six central administrative departments: official, household, ritual, military, criminal and industrial.
Responsible for the appointment, assessment and management of officials in the official department; The household department is in charge of household registration and fiscal revenue management; Ritual department is in charge of sacrifice, etiquette, education, imperial examination, etc. The Ministry of War is in charge of election, examination, military affairs, military affairs, etc. Military attache below level 6; The examination of the trial case of Dali Temple by the Ministry of Punishment and the joint trial of the case by officials in the capital; The Ministry of Industry is in charge of civil engineering, water conservancy projects, agriculture, forestry and animal husbandry (except military horses) and fisheries.
Each of the six departments has four branches, which are responsible for administrative affairs.
The establishment and perfection of the system of three provinces and six departments shows that the feudal administrative system is becoming more and more mature and stereotyped, which has a great influence on future generations.