The River Arrow (Welsh: Afon Arwy) is a river in the Welsh Marches, rising in Powys in Wales, then flowing into the English county of Herefordshire.

[1] It rises near Gwaunceste Hill, then flows south-east through Newchuch and Michaelchurch-on-Arrow.

It forms a short section of the England/Wales boundary, before flowing into Herefordshire, and through the town of Kington.

It proceeds east through Herefordshire, passing Lyonshall, Staunton-on-Arrow, Pembridge, Eardisland, Arrow Green, Monkland, Ivington, Broadward, and has its confluence with the River Lugg south of Leominster, at Stoke Prior.

The 56 km (35 mi) Arrow Valley Trail is a long-distance footpath following the river from its source to Leominster.