Jintan, known as Jinshan (金山) in ancient times, was a township of Yanling commandery since the reign of the Emperor Yuan of Jin.

Then it was promoted by its inhabitants as Jinshan county to strengthen the local vigilance in the late Sui dynasty, without permission.

As a densely populated area, the county was reestablished in about 688 under the Tang dynasty, but since there was a namesake in present-day Jinhua, Zhejiang, it was named after Jintan, a hill of Mao Mountain.

Western Jintan includes the mountainous region Maoshan, which covers an area of about 223 square kilometres (86 sq mi).

Flatlands lie in the east of Jintan, part of the Taihu Plain, with an area of about 752 square kilometres (290 sq mi).