Ernest Ivy "Boots" Thomas, Jr. (March 10, 1924 – March 3, 1945) was a United States Marine Corps sergeant who was killed in action on March 3, 1945 during the Battle of Iwo Jima in World War II. He was one of the Marines who raised the first United States flag and flagstaff on top of Mount Suribachi, on Iwo Jima, on February 23, 1945. He was posthumously awarded the Navy Cross for extraordinary heroism at Mount Suribach on February 21, 1945.