By querying the information of postal code library, the postal code of Maolin Town, Yongshan County, Zhaotong City, Yunnan Province is 657307 and the area code is 0870.

The first two digits of postal code indicate provinces (autonomous regions and municipalities directly under the Central Government), the third digit indicates postal areas (a province is divided into several postal areas, namely mail distribution and transportation networks), the fourth digit indicates counties (cities), and the last two digits indicate post offices and their delivery areas.