Carl Gustav Wilhelm Tham (born 5 July 1939) is a Swedish politician.

Until 1984, he was a member of Liberal People's Party, and since 1986, he is a Social Democrat.

He was minister for energy from 1978 to 1979 and member of the Riksdag (parliament) in 1976 and from 1979 to 1980.

Then he became director-general of the State Energy Agency (Statens energiverk), a position he held from 1983 to 1985 and of the Swedish International Development Cooperation Agency from 1985 to 1994.

He became education minister in 1994 and served in that capacity until 1998.