Tangvayosaurus is a genus of sauropod dinosaur from the Aptian-Albian age Lower Cretaceous Gres superieurs Formation of Savannakhet Province, Laos. It was a basal somphospondylan, about 15 m long, and is known from the remains of two or three individuals.

Euhelopodidae is a family of sauropod dinosaurs of disputed membership and affinities, which contains Euhelopus and its close relatives. Most proposed euhelopodids are from East Asia.