John Alexander (died about 1733) was a Scottish painter and engraver of the 18th century. He studied in Italy under the mastership of Giuseppe Bartolomeo Chiari.
Alexander was the son of a clergyman, and was descended from Jamisone. In the early part of the 18th century he visited Rome, about 1717, but was not established there, as Heineken says, and etched some plates after Raphael's frescoes in the Loggie of the Vatican. He dedicated a set of six, dated 1717 and 1718, to Cosimo III, Grand Duke of Tuscany; Strutt says that they do Alexander no kind of credit, and terms them slight, loose, and incorrect etchings. In 1721 a letter to a friend was printed at Edinburgh describing a staircase painted at Gordon Castle, with the Rape of Proserpine, by Alexander. This was based upon a work by his master, Chiari, in Palazzo Barberini.
- Long, George. The Biographical Dictionary of the Society for the Diffusion of Useful Knowledge. London: Longman, Brown, Green & Longmans, 1842–1844. 4 vols.