Parvosaurus is an extinct species of rhynchocephalian reptile known from the Late Triassic of Germany.

The specimen was discovered in the rock surrounding a specimen of Plateosaurus that had been collected from a brick pit located in Saxony-Anhalt between Halberstadt and Quedlinburg on the Bundesstraße 79 highway in sediments belonging to the Late Triassic (Norian) Arnstadt Formation by Werner Janensch in 1928.

The specimen was not discovered until the block was CT scanned as part of the redescription of the small reptile Elachistosuchus in 2015.

The specimen is thought to be a juvenile, as it has relatively large eyes and is small in size, with the skull only being around 1.6 centimetres (0.63 in) in length, comparable to that of Diphydontosaurus.

[1] Parvosaurus was placed as a basal sphenodontian by its describers, more derived than Diphydontosaurus but less derived than Planocephalosaurus[1]: Gephyrosaurus Diphydontosaurus Parvosaurus Planocephalosaurus Clevosaurus Neosphenodontia