Sir William Walter Carlile, 1st Baronet, OBE, DL, JP (15 June 1862 – 3 January 1950) was a British Conservative Party politician from Gayhurst in Buckinghamshire who served from 1895 to 1906 as the Member of Parliament (MP) for the Buckingham or (Northern) division of Buckinghamshire.
Carlile was the only son of James Walter Carlile of Ponsbourne Park in Hertfordshire and his wife Mar (née Whiteman) from Glengarr in Argyll. He was educated at Harrow and at Clare College, Cambridge, and later became a lieutenant of the 3rd Volunteer Battalion of the Oxfordshire Light Infantry (the former Royal Buckinghamshire Militia (King's Own)).
He held several offices in the county: as a Justice of the Peace, a Deputy Lieutenant (having been appointed in 1897), and an Alderman of Buckinghamshire County Council. In early 1900 he received a commission as major of the 1st Battalion, Buckinghamshire Rifle Volunteers.
Carlile first stood for Parliament at the 1892 general election, when he was defeated in Buckingham by the sitting Liberal Party MP Herbert Samuel Leon. He won the seat at the next election, in 1895, on a swing of 4.5%, and was re-elected in 1900. He stood down from the House of Commons at the 1906 general election, when Buckingham was won by the Liberal Frederick William Verney.