David Martin (1 April 1737 – 30 December 1797) was a Scottish painter and engraver. Born in Fife, he studied in Italy and England, before gaining a reputation as a portrait painter. Martin was the first of the five children of John Martin (1699/1700–1772), Anstruther Easter's parish schoolmaster, and his second wife, Mary Boyack (?1702–1783).

Martin accompanied his art teacher, the portrait painter Allan Ramsay on his tour of Italy in 1756–7, and after returning became a student at the St Martin's Lane Academy in London. There he gained premiums for life drawing in each year from 1759 to 1761. He also joined Ramsay's studio in the 1760s as its principal draughtsman, helping to produce many of the coronation portraits of George III and Queen Charlotte.

Martin had his own studio by 1770, by which time he had also produced his first self-portrait (now in the National Gallery of Scotland). It shows him with a clear fair skin, wavy ginger hair, aquiline nose and small red lips. Martin painted over 300 portraits in his lifetime. One of the earliest independent ones is that of Benjamin Franklin (now in the White House, Washington, DC), painted in 1767. His most influential works depict Scottish Enlightenment figures like the chemist Joseph Black (1787, Scottish National Portrait Gallery) and the philosopher David Hume (1770, now in a private collection), and noblewomen such as the Honourable Barbara Gray (1787). His Dictionary of National Biography entry states that "He portrayed his sitters with integrity in an honest natural style, thereby consolidating a recognizably Scottish tradition of portraiture". Martin exhibited at the Incorporated Society of Artists from 1765 to 1777 (being elected its treasurer, vice-president, and president between 1772 and 1777), at the Free Society of Artists in 1767 and at the Royal Academy in 1779 and 1790. He is listed in 1766 as a member of the Society for the Encouragement of the Arts, Manufactures and Commerce, as "History Painter, living in Soho Square".