Monnow Mill is a former watermill on the river Monnow in Osbaston on the Osbaston road in Monmouth, Wales.

The building has been a Grade II Listed since 1974.

[1] The present four-storey house, dates from the early nineteenth century and still has a weir in the Monnow, with a very short leat.

[2] However, in the early 20th century the mill was used as a machine shop, manufacturing small parts for cars and motorcycles such as Morris Motors[3] The Mill originally had a house and outbuildings on the opposite side of the road.

Monnow Mill, house, mill and outbuildings were owned by the 9th Duke of Beaufort and formed part of his estate in 1901 when they were listed for auction.