Wumengosaurus is an extinct aquatic reptile from the Middle Triassic (late Anisian stage) Guanling Formation of Guizhou, southwestern China. Originally described as a basal eosauropterygian, and usually recovered as such by recent phylogenetic analyses, one recent phylogeny has placed it as the sister taxon to Ichthyosauromorpha while refraining from a formal re-positioning.