Johan Wilhelm Zetterstedt (20 May 1785 – 23 December 1874) was a Swedish naturalist who worked mainly on Diptera and Hymenoptera.
Zetterstedt studied at the University of Lund, where he was a pupil of Anders Jahan Retzius. He received the title of professor in 1822 and succeeded Carl Adolph Agardh as professor of botany and practical economy in 1836, retiring as emeritus in 1853. In 1831, he was elected a member of the Royal Swedish Academy of Sciences.
He is best known as an entomologist. His collections of Scandinavian, Lapland and world Diptera and Orthoptera are in the Zoological Museum of the University of Lund. His students include Anders Gustaf Dahlbom.