Alexander Stewart (c.1214-c.1283) was the hereditary High Steward of Scotland from c.1241 until his death. He was a member of the House of Stewart (later known as Stuart).

Alexander was a son of Walter Stewart, 3rd High Steward of Scotland and his wife Beatrix of Angus. Beatrix was daughter of Gilla Críst of Angus.

Alexander attended St. Louis of France to the Holy War, and he was the principal commander under King Alexander III at the Battle of Largs October 2, 1263 when the Scottish army defeated the Norwegians. He received from Alexander III a grant of the Barony of Garlies in Galloway on November 30, 1263.  In 1264 he invaded the Isle of Man.

Alexander Stewart was married to Jean MacRorie, daughter and heiress of James MacRorie, Lord of Bute and Arran, son of Angus MacRorie, Lord of Bute. They were parents to at least three children:
• James Stewart, 5th High Steward of Scotland (c. 1243 - 1309.
• Sir John Stewart, Lord of Bonkyl (before 1269 - 1298). Killed while fighting in the Battle of Falkirk.
• Elizabeth Stewart.

Through their eldest son James, Alexander and Jean were the great-grandparents of King Robert II, the first Stewart to be King of Scots, and thus an ancestor of all subsequent Scottish monarchs and the later and current monarchs of Great Britain.

Alexander and Jean were also the direct male-line ancestors, through their second son, of Henry Stuart, Lord Darnley.