Alexander Macdonald FSA Scot (c. 1791 – 1850) was a Scottish antiquary.
In early life, Macdonald was employed in the Register House, Edinburgh, where he assisted Thomas Thomson in the preparation of the Acts of the Scottish Parliament and other works.
In 1836 he was appointed principal keeper of the register of deeds and probate writs.
He had supplied material for Sir Walter Scott's notes to the Waverley Novels.
[1] Macdonald is best known as editor of the publications of the Maitland Club.