Johannes Theodor Reinhardt (3 December 1816, in Copenhagen – 23 October 1882, in Frederiksberg) was a Danish zoologist and herpetologist.

He was an early supporter of Charles Darwin’s theory of evolution, and from his research of extinct species, was critical of George Cuvier's concept of "anti-evolutionary catastrophism".

[1] With Christian Frederik Lütken (1827–1901), he was co-author of Bidrag til Kundskab om Brasiliens Padder og Krybdyr (Contributions to the knowledge of Brazilian amphibians and reptiles).

[3] In 1848, Hermann Schlegel named the Calabar "python", Calabaria reinhardtii, in his honor.

[4][5] Reinhardt's caecilian, Mimosiphonops reinhardti, was named for him in 1992, more than 100 years after he had collected the holotype.