Sir Ivar Iain Colquhoun, 8th Baronet, JP, DL (4 January 1916 – 31 January 2008) was a British noble.
Sir Ivar the son of Sir Iain Colquhoun, 7th Baronet and his wife Geraldine Bryde (Dinah) Tennant. He was educated at Eton.
He was working at a lumber camp in Finland at the outbreak of World War II, and joined a Territorial Army battalion of the Argyll and Sutherland Highlanders as a private soldier. When the Soviet Union invaded Finland in November 1939, he was seconded to the 5th (Ski) Battalion Scots Guards. This was disbanded after Finland was forced to accept Russian terms in March 1940. Then he joined the artillery in Libya and served there during the siege of Tobruk, later to become the subject of some of his drier reminiscences. By the end of the war, he served as a liaison officer with the Grenadier Guards and subsequently a captain in the Coldstream Guards.
He served as a Justice of the Peace for over twenty years. He was a deputy lieutenant for Dunbartonshire and for twenty years was the chairman of the British Sailors' Society.
He was the eighth baronet and the 30th Laird of Luss. As a member of the Standing Council of Scottish Chiefs, he made regular appearances at clan gatherings and clan games and endorsed the clan museum. From 1949 until 1982, he was chieftain of the Luss Highland Games in July.