Diplotomodon (meaning "double cutting tooth") is a dubious genus of reptile, possibly a theropod dinosaur, from New Jersey. Diplotomodon is only known from a single tooth, holotype ANSP 9680, found near Mullica Hill in either the Navesink or Hornerstown Formation, marine deposits dating to the Maastrichtian stage of the late Cretaceous period. Joseph Leidy originally described the tooth using the name Tomodon in 1865, considering it a carnivorous marine reptile, probably a plesiosaur.