Coombe Keynes is a hamlet and civil parish in the Purbeck district of the English county of Dorset. It is situated about 5 miles (8.0 km) west-south-west of Wareham. In 2013 the estimated population of the civil parish was 80. There are 22 houses in the hamlet itself and 37 properties across the parish as a whole. Coombe Keynes was historically part of the Winfrith Hundred. It appears in the Domesday Book (as Cume), when it was held by Gilbert de Magminot, Bishop of Lisieux. The name Keynes derives from the later Lords of the Manor, the de Cahaignes family, who also held Tarrant Keyneston.