Sphenotitan is an extinct genus of rhynchocephalian reptile, known from the Late Triassic (Norian) Quebrada del Barro Formation of Argentina.

[2] It was a large-sized sphenodontian, with an estimated skull length of over 10 centimetres (3.9 in).

The skull is roughly triangular in shape, and had large upper temporal fenestrae.

The premaxillae form a beak, with a cutting edge similar to a chisel.

The teeth of Sphenotitan, like other elienodontines, were large and wide, and designed for shredding vegetation, with blade-like palatal teeth on the roof of the mouth.