according to the information in the postcode database, the postcode of Longkou City, Yantai City, Shandong Province is 2756. The first two digits 27 represent Shandong Province, the third digit 5 represents Yantai City, the fourth digit 6 represents Longkou City, and the last two digits represent the specific delivery area.

Longkou City, a county-level city under the jurisdiction of Shandong Province, is managed by Yantai City. In 1986, with the approval of the State Council, Huangxian County was revoked and Longkou City was established. There are railway trunk lines such as Dalailong Railway and Longyan Railway in the territory.