Colonel Michael Guy Percival Willoughby, 11th Baron Middleton, KG, MC, TD, ED (21 October 1887–16 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. Graduating on 9 October 1907, he 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.