Hải Lăng is a rural district located in the Quảng Trị province of Vietnam's North Central Coast region. The district covers a total area of 291 km2 (112 sq mi) and serves as a rural administrative division within the province.
The district capital is situated at Diên Sanh. As of 2003, the population of Hải Lăng was recorded at 100,854 residents.