John James Hamilton Dalrymple, 12th Earl of Stair, KT, DSO, DL (1 February 1879 – 4 November 1961), styled Viscount Dalrymple between 1903 and 1914, was a Scottish soldier and Conservative Party, later Unionist Party, politician.
The son of John Dalrymple, 11th Earl of Stair, Dalrymple was commissioned a second lieutenant in the Scots Guards on 16 February 1898, and promoted to lieutenant on 11 October 1899. He fought in the Second Boer War, where he took part in the march to occupy the Boer capitals Bloemfontein (March 1900) and Pretoria (June 1900), and was present at the successive Battles of Diamond Hill (11-12 June 1900) and Bergendal (21-27 August 1900).
Following the end of hostilities in early June 1902, he left Cape Town on board the SS Orotava, and arrived at Southampton the next month. He later fought in the First World War, where he was captured by the Germans.
Lord Dalrymple sat as Member of Parliament for Wigtownshire from 1906 to 1914, when he succeeded his father in the earldom and entered the House of Lords. Lord Stair was later Lord High Commissioner to the General Assembly of the Church of Scotland in 1927 and 1928.