China began to formulate the postal code of China from 1974. After about five years, the National Postal Code Trial Scheme was worked out and carried out in Liaoning, Shanghai, Jiangsu and other provinces and cities 1978. 1 980 July1officially promoted and implemented in the whole country. Later, for various reasons, the implementation work stopped completely. Until 1986, the National Postal Work Conference decided to re-implement postal codes throughout the country. The current postal code in China is "four levels and six codes". That is, each group of codes consists of six Arabic numerals, representing four levels: provinces (autonomous regions and municipalities directly under the Central Government), postal districts, county (city) post offices and delivery offices (districts). The first two digits of the six figures represent provinces (autonomous regions and municipalities directly under the Central Government), the third represents postal areas, the fourth represents county (city) post and telecommunications offices, and the last two digits are delivery office (district) numbers.