William Gamble (1 January 1818 – 20 December 1866) was a civil engineer and a United States Army cavalry officer.

He commanded one of two brigades in Brigadier General John Buford's Division of Cavalry, in which he played an important role in defending Union positions during the first day of the Battle of Gettysburg.

After the start of the Civil War, Gamble was appointed lieutenant colonel of the 8th Illinois Cavalry regiment on 18 September 1861.

Gamble's regiment was attached to the Pennsylvania Reserve Division and fought in the Peninsula Campaign, where he was wounded in the chest, leading a cavalry charge against rebel pickets more than a month after the end of the Seven Days Battles.

After recovering from his wound, Gamble was promoted to colonel on 5 December 1862, just before the Battle of Fredericksburg, but his regiment saw no action in that fight.

During the Gettysburg Campaign, Gamble continued on leave and missed the largest predominantly cavalry battle of the war, Brandy Station.

The officer in temporary command of his brigade, Colonel Benjamin Franklin Davis, was killed there, and Gamble returned to the field on 13 June 1863.