| Named By: | Peyer in 1955 |
| Time Period: | Middle Triassic, 242 Ma |
| Location: | Europe, Switzerland |
| Size: | Uncertain |
| Diet: | Probably shellfish |
| Fossil(s): | Almost complete remains |
| Classification: | | Chordata | Reptilia | Sauropsida | Diapsida | Archosauromorpha | |
Helveticosaurus is an extinct genus of diapsid marine reptile known from the Middle Triassic (Anisian-Ladinian boundary) of southern Switzerland. It contains a single species, Helveticosaurus zollingeri, known from the nearly complete holotype T 4352 collected at Cava Tre Fontane of Monte San Giorgio, an area well known for its rich record of marine life during the Middle Triassic.