An iron maiden is a presumed torture device, consisting of an iron cabinet with a hinged front and spike-covered interior, sufficiently tall to enclose a human being. It is believed to be fictional, although examples have been created for display.

The iron maiden is often associated with the Middle Ages. However, no account has been found earlier than 1793, although medieval torture devices were catalogued and reproduced during the 19th century. Wolfgang Schild, a professor of criminal law, criminal law history and philosophy of law at the University of Bielefeld, has argued that supposed iron maidens were pieced together from artifacts found in museums, to create spectacular objects intended for (commercial) exhibition.

The most famous iron maiden was that of Nuremberg, first displayed possibly as far back as 1802. The original was lost in the Allied bombing of Nuremberg in 1944. A copy "from the Royal Castle of Nuremberg," crafted for public display, was sold through J. Ichenhauser of London to the Earl of Shrewsbury in 1890 along with other torture devices, and, after being displayed at the World's Columbian Exposition, Chicago, 1893, was taken on an American tour. This copy was auctioned in the early 1960s and is now on display at the Medieval Crime Museum, Rothenburg ob der Tauber.

Historians have ascertained that Johann Philipp Siebenkees created the history of it as a hoax in 1793. According to Siebenkees' colportage, it was first used on August 14, 1515, to execute a coin forger. It was built in the 19th century as a probable misinterpretation of a medieval "Schandmantel" ("mantle of shame"), which was made of wood and tin but without spikes.

A crude copy was supposedly found among the palace effects of Uday Hussein in Iraq. Several nineteenth-century iron maidens are on display in museums around the world, but it is unlikely that they were ever employed.