Jack Richard Miller (June 6, 1916 – August 29, 1994) was an American politician and jurist who served as a Republican United States Senator from Iowa for two terms from 1961 to 1973.

In World War II, Miller served with the United States Army Air Corps from 1942 to 1946, attaining the rank of lieutenant colonel.

During this time his military service included the China-Burma-India Theater, the faculty at the Army Command and General Staff College at Fort Leavenworth, Kansas, and duty at Air Force Headquarters in Washington, D.C. After the war, Miller received his Juris Doctor from Columbia Law School in 1946, and did postgraduate study at University of Iowa College of Law later that year.

In a race to replace the retiring Republican Senator Thomas E. Martin, Miller defeated Iowa's sitting governor, Herschel C. Loveless, in a close contest.

During a phone call in the early hours of the morning following that election, President Nixon told Henry Kissinger that "we lost Jack Miller because he's a jackass.