Colonel Harvey Curtiss Barnum, Jr. (born July 21, 1940), is a retired United States Marine Corps officer who received the Medal of Honor for valor during the Vietnam War. He was the fourth Marine to receive the medal for valor in Vietnam. He retired from the Marine Corps in 1989 after more than 27 years of service. Barnum served as Deputy Assistant Secretary of the Navy for Reserve Affairs from July 23, 2001 to January 20, 2009. He also served as Acting Assistant Secretary of the Navy (Manpower and Reserve Affairs) from January 21, 2009 to April 30, 2009.