Kustaa Gideon Vilkuna (26 October 1902 – 6 April 1980) was a Finnish ethnologist, linguist and historian.
He was appointed a professor of ethnology at the University of Helsinki in 1950.
In politics, he was a member of the Agrarian League and the Minister of Education in Reino Kuuskoski's cabinet.
He was also closely associated with then-president Urho Kekkonen, being even described as the éminence grise of Kekkonen.His grandsons Janne Vilkuna and Kustaa H.