Walter of Douai (Old Norman: Wautier de Douai) (born c.1046, died: c.1107) was a Norman knight, probably at the Battle of Hastings, and a major landowner in South West England after the Norman Conquest, being feudal baron of Bampton in Devon and of Castle Cary in Somerset. He is given various names and titles in different sources including: Walter (or Walschin or Walscin) de Douai. Douai is sometimes written as Dowai. He has also been called Gautier de Douai and later Walter the Fleming.