Nga Sơn District
（重定向自Nga Son）
Nga Sơn is a district (huyện) of Thanh Hóa Province in the North Central Coast region of Vietnam.
As of 2003 the district had a population of 148,676. The district covers an area of 151 km². The district capital lies at Nga Sơn.
The district is located in the northeast province Thanh Hóa and Thanh Hóa city about 42 km, north and east borders Ninh Bình Province, the western border with Hà Trung District, south of Hậu Lộc District borders. Plain terrain, located from Tam Điệp mountains at the north to the south, the east borders the sea. The Len river has flowed through the southern district.