Rhadinosaurus (meaning "slender lizard") is a genus of nodosaurid ankylosaur first described in 1881 by Harry Govier Seeley, based on remains uncovered in Austria sometime between 1859 and 1870 by Edward Suess and Pawlowitsch.

[1] It was a herbivore that lived around 84.9 to 70.6 million years ago (during the Late Cretaceous period).

The fibulae (PIUW 2349/34), which are clearly ankylosaurian, were originally identified as femora in the original description, but were eventually re-identified in a 2001 review of ankylosaur specimens from the Grünbach Formation.

[3] Sachs and Hornung (2006) re-identified one of the putative humeral bones (PIUW 2348/35) as a tibial fragment of an rhabdodontid ornithopod dinosaur, referring it to Zalmoxes sp.

[4] Rhadinosaurus was initially classified as a dinosaur of uncertain position, and later considered an ornithosuchid as well as possible synonym of Doratodon, until Franz Nopcsa introduced the now popular theory that classifies it as a probable synonym of Struthiosaurus.