Claës Efraim Günther (29 or 30 December 1799 – 23 July 1861) was a Swedish politician and jurist who served as Prime Minister for Justice between 1856 and 1858.
Günther first entered politics acting as a representative of the nobility at the Riksdag of the Estates in 1828.
During the Riksdag of 1844–1845, Günther came to be known as an avid advocate for reforming the penal code as well as one of few members in the House of Nobility to argue in favour of equal inheritance rights between men and women.
In response to the March Unrest of 1848, king Oscar I appointed Günther to serve as minister without portfolio in the Council of State.
In 1856, Günther was reinstated in the government, this time as Prime Minister for Justice, an office he held until 1858 when he was forced to resign due to pressures from the Crown Prince.