In the early Tang Dynasty, the Sui system was followed. In the third year of Emperor Wude's reign (620 AD), Nayan was renamed Shizhong, and the name of Neishu Sheng was changed to Zhongshu. Zuo and You Pushe are the governors of Shangshu Province, and they are prime ministers together with Shizhong and Zhongshu Ling.

The master of the Zhongshu family makes decisions and issues orders, the masters of the sect review the approval and refutations, and the master of the secretariat executes the decrees. The powers and responsibilities are clear. However, since there is one master of the sect who issues orders and one master of deliberation, it is inevitable that each has his or her own opinions. Seeing what happened, Taizong set up a "Zhengshi Hall".

Considering that the political affairs hall was the place where government was discussed, it became the center of actual decision-making, so Zhongshu Ling and his subordinates became the real prime ministers.

On behalf of the Zhengshitang, the servants on the left and right of the Minister should hold the title of "Tongzhongshumenxiapingzhangshi" or "Tongzhongshumenxiasanpin", etc., which means they will have the status of true prime minister and hold meetings in the Zhengshitang. .

In the Tang Dynasty, except for the chief ministers of the three provinces who were ex officio prime ministers, anyone who added "the same three grades" and "the same level of affairs" were all prime ministers, without any distinction.

The founding spirit of the Tang Dynasty's prime ministership system was to be cautious in the administration of affairs on the one hand; on the other hand, it was to prevent the monarch and powerful ministers from being arbitrary. Therefore, all government orders were drafted by Zhongshu, and after being reviewed by his subordinates, the emperor could not easily change them. , and "without passing through Fengge (Zhongshu) Luantai (under the door)", it is not the imperial edict (Zi Zhi Tong Jian Tang Ji), which fully demonstrates the spirit of the above-mentioned system.

The powers and responsibilities of the three provinces are clearly defined. Any major affairs of a single country will be drafted by Zhongshu Quan first. After being ordered by Zhongshu, after the decision is made and reviewed, the plan will be submitted and the edict will be issued; it will be sent to the province for refutation. then send it to the minister for execution, so the monarch and powerful ministers have no right to make arbitrary decisions.

The prime ministers of the Tang Dynasty adopted a committee system, which was different from the leadership system of the Han Dynasty. The government had three yamen: Zhongshu, Menxia, ??and Shangshu. The functions of these three departments plus the Yushitai were equal to those of the Han Dynasty. The powers of the prime minister. This shows the decentralization of powers among the prime ministers in the Tang Dynasty.

1. Zhongshu Sheng----issue orders. These orders were called "imperial edicts" in the Tang Dynasty. Although they were issued in the name of the emperor, they were not drafted by the emperor but by Zhongshu Sheng.

The procedure is as follows: Zhongshu Sheren drafts multiple copies of the imperial edict, called the "Wuhua Judge", and then Zhongshu Ling (Zhongshu Provincial Governor) or Zhongshu Shilang (Zhongshu Provincial Adjutant) selects the edict. A copy was issued and slightly polished to become a formal edict, and then the emperor drew the word "imperial edict" to become the emperor's order, and finally it was issued to the provinces.

2. The province under the door----review. The emperor's order issued by the Zhongshu Province must be reviewed. If the review fails, it will be returned to the Zhongshu Province with an annotation by Gai Shizhong (an official with the power to refute), which is called "Tugui".

This means that the edict is required to be re-drafted by the Ministry of Secretariat. If the re-examination is passed, it will need to be signed by Shizhong (the governor of the province) or Shilang (the adjutant of the province) before the edict will officially take effect, and then be sent to the Ministry of Secretariat for execution. It was considered illegal in the Tang Dynasty if the emperor issued an order directly without a Zhongshu or a family seal.