Øistein Saksvik (7 January 1925 – 10 November 1998) was a Norwegian long-distance runner. He specialized in the 5,000-metre and the 10,000-metre runs, as well as in cross-country running. At the 1952 Olympic Games, he competed in the 5,000-meter run. Saksvik became the Norwegian champion twenty times, a national record. In addition, he captured three Norwegian records in long-distance running from Martin Stokken, and held onto them for some years each. In the late-1950s, Saksvik's dominance in Norwegian long-distance running was eclipsed by Tor Torgersen and fellow Ranheim club member Ernst "Kruska" Larsen, later Thor Helland.
Saksvik competed in several international championships. In his first, the Olympic 5000 metres in 1952, he did not progress from the heats. However, at the 1954 European Championships, he finished seventh in both 5000 and 10,000 metres. He later finished fourteenth in the 10,000 metres at the 1958 European Championships.
Saksvik is also known for winning twenty Norwegian championship titles in athletics, a Norwegian record which is tied with thrower Knut Hjeltnes. On the track he became Norwegian champion in the 5000 metres in 1950, 1952, 1953, 1954 and 1957, alternating mostly with cityfellows Martin Stokken and Ernst "Kruska" Larsen. He also won silver medals in this distance in 1949, 1951 and 1955. He won the 10,000 metres in 1953, 1954, 1956 and 1957. By winning his first gold medal, Saksvik ended the six-year dominance of Martin Stokken. However, in 1958 Saksvik only won the silver, behind club fellow Ernst "Kruska" Larsen.