Alexander Keiller was a Scottish heir, archaeologist and antiquarian best known for his excavations, restoration work and preservation efforts at Avebury in Wiltshire. He acquired Avebury Manor in 1934 and developed the modern archaeological presentation of the Avebury monument complex.

His ownership concerned Avebury Manor and the associated historic estate and archaeological landscape; it should not be treated as proof of ownership of every historical territorial right attached to the medieval manor.