Alexander Stuart FRS FRCP (1673–1742) was a British natural philosopher and physician. He was born in Aberdeen, Scotland. He graduated from Marischal College, University of Aberdeen, in 1691 with an MA and became a ship's surgeon, serving on the London from 1701 to 1704 and on the Europe from 1704 to 1707. While at sea he kept records of his operations and sent specimens of new creatures to Hans Sloane, with several reports on such animals being published in the Philosophical Transactions of the Royal Society.