Eynsham Abbey was a Benedictine monastery in Eynsham, Oxfordshire, in England between 1005 and 1538. King Æthelred allowed Æthelmær the Stout to found the abbey in 1005. There is some evidence that the abbey was built on the site of an earlier minster, probably founded in the 7th or 8th centuries. The site is a Scheduled Historic Monument.