Lusitanosaurus (meaning "Portuguese lizard") is a genus of reptile from the Sinemurian stage of Early Jurassic of Portugal, maybe from the Coimbra Formation.

It was considered the second example of the Dinosaurian group Thyreophora from the Sinemurian of Europe and it the oldest known dinosaur from the Iberian Peninsula, but this affinity has been contested.

It is based on a large left maxilla with teeth that was lost in the fire at Museu Nacional de História Natural e da Ciência, Lisbon, in 1978.

The teeth were described to be similar to those of Scelidosaurus, which approaches it narrowly by the presence of important anterior and posterior basilar points on each tooth.

[7] The São Pedro de Moel rocks consists on calcareous strata, mostly from Marginal Marine environments belonging to the Coimbra Formation.