State Archives Administration

State Archives Administration (Chinese: 国家档案局 or Chinese: 中央档案馆), founded 1954, is the national administrative agency responsible for historical records of the state dating back to imperial times in China. These include government documents since the May Fourth Movement. The archive collections include more than 800,000 records. There are more than 80 million items of information in documents, records, files, manuscripts on important political figures. The agency also concurrently holds records for the Communist Party of China. Hence it is also known as the Central Archives.

More information on the Wikipedia page

The website, in Chinese, is