Barnwell Manor is a Grade II listed country estate near the village of Barnwell, about 2.5 miles (4.0 km) south of Oundle, in Northamptonshire, England. The historic former home of the Duke and Duchess of Gloucester, as of 2017 it was occupied by Windsor House Antiques. In September 2022, Prince Richard, Duke of Gloucester, put the manor up for sale for £4.75 million.

Barnwell is a village in North Northamptonshire in England, 2 miles (3.2 km) south of the town of Oundle, 78 miles (126 km) north of London and 14 miles (22.5 km) south-west of Peterborough. The River Nene runs north of the village, separating it from Oundle.