Colonel Michael Guy Percival Willoughby, 11th Baron Middleton KG MC TD ED (born 21 October 1887, died 16 November 1970) was a British peer and soldier.
Willoughby was the second son of Godfrey Willoughby, 10th Baron Middleton and was educated at Wellington College and the Royal Military College.
In 1936, Willoughby was appointed Lord Lieutenant of the East Riding of Yorkshire. From 1931, he was President of University College, Hull, (later the University of Hull) and was its first Chancellor from 1954 to 1970.
Graduating from the Royal Military College on 9 October 1907, Willoughby was commissioned a second lieutenant in the South Lancashire Regiment (The Prince of Wales's Volunteers). He transferred to the 17th Lancers 26 October 1907 and on 26 October 1909 to the 10th Duke of Cambridge's Own Lancers (Hodson's Horse) of the Indian Army. He was promoted lieutenant 9 January 1910.
Willoughby was stationed in India at the outbreak of the First World War, as the regiment was not selected to go overseas, but in March 1915 he was sent to Mesopotamia attached to the 16th Cavalry, being promoted acting captain on 1 June 1915 and temporary captain 1 September 1915. He also served as the 6th Cavalry Brigades Machine Gun officer January to June 1916 before returning to the 16th Cavalry. In July 1916 he was attached to the 12th Cavalry until August when he returned to India to take over the 10th Duke of Cambridge's Own Lancers (Hodson's Horse) depot at Multan, that regiment now being selected for active service. For his service in Mesopotamia he was awarded the Military Cross (The London Gazette 22 December 1916) and was mentioned in dispatches three times (The London Gazette 5 April 1916, 19 October 1916 and 12 June 1917). He was promoted from acting captain to captain 9 October 1916, later to be antedated to 1 September 1915. While at Multan he led two scratch squadrons of the regiment on the Marri punitive expedition between March and April 1918 and appointed acting major commanding the depot 28 January to 12 August 1918. He was relieved of command of the depot in August 1918. He was acting major again whilst second in command of a regiment 26 October 1918 to 11 February 1919 and promoted brevet major 3 June 1919 and major 9 October 1922.