In 1951, entire country was basically liberated, and new administrative divisions were initially established. At that time, country was divided into six administrative regions: North China, Northeast China, East China, Central South China, Southwest China and Northwest China. There are provinces, municipalities directly subordinate to central government, autonomous regions, administrative regions, etc. within large administrative regions, and the administrative division system has not been standardized and improved.

From 1952 to 1954, a comprehensive adjustment was carried out. Major adjustments:

From 1955 to 1968, administrative division was slightly changed. Main content:

From 1969 to 1978, influenced by deterioration of Sino-Soviet relations (the Soviet Union claimed to have created incidents in Inner Mongolia), the main adjustment during this period was dismantling of Inner Mongolia. In 1969, most of Hulunbier League was transferred to Heilongjiang Province; Tuquan County and right front banner of Horqin were transferred to Jilin Province; The Zhaowood League was transferred to Liaoning Province; parts of left Alha banner and right Alha banner were given to Ningxia Hui Autonomous Prefecture. Region; The Bayannaoer League was placed in Gansu province and so on.

In 1979, China was reformed and opened up. Relations between China and Soviet Union gradually eased, so administrative division of Inner Mongolia returned to its previous state. In 1988, in order to promote reform and opening up, a special economic zone was established in Hainan, and at same time, Hainan Province was established.

1. In 1990s, in order to promote opening up of western region and resettlement of immigrants from Three Gorges, Chongqing Municipality was established in 1997. The three cities of Chongqing, Wanxian, Fuling, and Qianjiang District in Sichuan Province are being gradually drawn into new municipalities directly under central government.
2. In 1997, Hong Kong returned to China and established Hong Kong Special Administrative Region. In 1999, Macau returned to China and formed Macau Special Administrative Region.