The Leman Baronetcy, of Northaw in the County of Hertford, was a title in the Baronetage of England. It was created on 3 March 1665 for William Leman, Member of Parliament for Hertford. The second Baronet also represented this constituency in the House of Commons. The title is believed to have become extinct on the death of the fourth Baronet in 1762, although it was claimed by supposed descendants of the first Baronet in the 19th century.