Sir George Mackenzie of Rosehaugh (1636‑1691) was a Scottish lawyer and legal writer.

Mackenzie was the son of Sir Simon Mackenzie, of Lochslin, a brother of the Earl of Seaforth. He was educated at St. Andrews, King's College, Aberdeen, and Bourges, called to the Bar in 1659, and in 1677 became Lord Advocate, in which capacity he was the subservient minister of the persecuting policy of Charles II in Scotland. The inhumanity and relentlessness of his persecution of the Covenanters gained him the nickname of "Bluidy Mackenzie (Bloody Mackenzie)". In private life, however, he was a cultivated and learned gentleman with literary tendencies, and is remembered as the author of various graceful essays, of which the best known is A Moral Essay preferring Solitude to Public Employment (1665). He also wrote legal, political, and antiquarian works of value, including Institutions of the Law of Scotland (1684), Antiquity of the Royal Line of Scotland (1686), Heraldry, and Memoirs of the Affairs of Scotland from the Restoration of Charles II , a valuable work which was not published until 1821. Mackenzie was the founder of the Advocates' Library in Edinburgh. He retired at the Revolution to Oxford. He died at Westminster on 8 May 1691 and was buried in Greyfriars kirkyard in Edinburgh.