Alexander MacDonnell

Alexander MacDonnell may refer to:


 * Sir Alexander Macdonnell (died 1634), of the Macdonnell baronets of Maye
 * Sir Alexander Macdonnell, 1st Baronet (1794–1875), of the Macdonnell baronets of Kilsharvan
 * Alexander MacDonnell, 3rd Earl of Antrim (1615–1699)
 * Alastair Ruadh MacDonnell (c. 1725–1761), also called Alexander
 * Alexander Macdonell (bishop of Kingston) (1762–1840), first Roman Catholic bishop of Kingston, Upper Canada