Weymouth Back River
General data
- Name: Weymouth Back River
- Water system: Atlantic Ocean
- Water type: River
- Progression: Hingham Bay -> Boston Harbor -> Massachusetts Bay -> Gulf of Maine -> Atlantic Ocean -> Planet Earth
- Climates: Temperate
- Continents: North America
- Countries: United States of America
The Weymouth Back River, sometimes called Back River, is a short, primarily tidal river in Hingham and Weymouth, Massachusetts, about 10 miles (16 km) south of Boston. It arises from a number of tributaries in ponds and swamps, such as Whitmans Pond, flows northward, and empties into Hingham Bay just south of Grape Island and Slate Island.