Plinthogomphodon is an extinct genus of traversodontid cynodonts from the Late Triassic of the eastern United States.

Fossils have been found from the Deep River basin of North Carolina, part of the larger Newark Supergroup.

The name alludes to the close proximity of the holotype specimen to the remains of a rauisuchian (Postosuchus alisonae) and a sphenosuchian archosaur (Dromicosuchus) when it was first discovered.

It is thought that the Plinthogomphodon had been previously consumed by the Postosuchus, which died and was buried when pursuing the Dromicosuchus.

[1] The holotype only preserves the underside of the snout, as the dorsal surface has eroded away.