Carl Gustav Calwer (11 November 1821, Stuttgart — 19 August 1874, Mineralbad Berg) was a German entomologist who specialised in Coleoptera.
He wrote initially with the Stuttgart professor Dr Gustav Jäger Käferbuch, Naturgeschichte der Käfer Europas published by Julius Hoffmann, Stuttgart a 666 page work with 50 lithographic plates all but two in colour. This very popular work was successively reprinted until 1916.