Anoplosaurus (meaning "unarmored or unarmed lizard") is an extinct genus of herbivorous nodosaurid dinosaur, from the late Albian-age Lower Cretaceous Cambridge Greensand of Cambridgeshire, England.

The generic name, derived from the Greek hoplo~, a word element used in combinations, with the meaning of "armed", refers to the fact no armour plates had been discovered.

[2][3][4] Although Seeley assigned Anoplosaurus to a general Dinosauria, he understood its possible affinities with Scelidosaurus or Polacanthus, as shown by the genus name, and other workers began to see it as an armored dinosaur.

[8] This suggestion led to considerable confusion, with some authors beginning to classify Anoplosaurus under the Camptosauridae,[9] a practice that was continued over several decades (with modifications as iguanodontian taxonomy changed over the years).

They wrote that it all belonged to a "primitive" or basal member of the Nodosauridae, the lack of armor possibly due to the young age of the animal at death.