Keith Hector Turnbull (28 December 1907 – 4 September 1978) was an Australian politician.
He was born in Bendigo to farmer Walter Turnbull and Margaret Gunning.
He served in the AIF during World War II and around 1940 married Olive Jean Mellis, with whom he had five children.
In 1950 he was elected to the Victorian Legislative Assembly as the Liberal and Country Party member for Korong.
His cousin Campbell Turnbull and son-in-law Charles Hider were also members of the Victorian Parliament.