Mary Maxwell may refer to:
- Mary Maxwell (Bahá'í), Rúhíyyih Khanum, Baha'i Hand of the Cause of God, and wife of Shoghi Effendi
- Mary Maxwell, wife of Charles Stuart, 4th Earl of Traquair
- Mary Maxwell Gates, mother of Bill Gates
- Mary Beth Maxwell, founding executive director of American Rights at Work
- Mary Maxwell (writer), née Mary Elizabeth Braddon