Olin Richard Branstetter (June 30, 1929 – November 17, 2011) was an American businessman and politician. Branstetter was born in Harmon, Oklahoma and grew up in Arnett, Oklahoma. He graduated from Oklahoma State University (OSU) with a degree in agriculture in 1952. He was a Korean War veteran. Branstetter was involved in the real estate and oil production businesses. He served in the Oklahoma State Senate.