Shengsi County is a county in the northeast of Zhejiang province in China consisting of an archipelago islands located to the east of Hangzhou Bay.

It is under the administration of Zhoushan City and is the easternmost county-level division in the province.

The islands of Greater and Lesser Yangshan are connected with Shanghai's Pudong New Area by the Donghai Bridge and their port forms part of the Port of Shanghai.

The county consists of 630 islands and islets, of which 13 have more than 100 inhabitants.

[1] Towns:[2] Townships: This Zhejiang province location article is a stub.