Woolsthorpe-by-Colsterworth (to distinguish it from Woolsthorpe-by-Belvoir in the same county) is a hamlet in the South Kesteven district of Lincolnshire, England, within the civil parish of Colsterworth.

Woolsthorpe-by-Colsterworth is 1 mile (2 km) northwest of the village of Colsterworth on the A1 road.

In 1973 the local quarries closed due to competition from imported iron ore.

The same year the Great Northern Railway's High Dyke branch line closed – it was opened in 1916 to carry iron ore, and lay to the north of the village.

Woolsthorpe Manor, Newton's birthplace, is a typical 17th-century yeoman farmer's limestone house, with later farmyard buildings.