| Named By: | Henry Fairfield Osborn in 1917 |
| Time Period: | Late Cretaceous, 77 Ma |
| Location: | Canada, Alberta - Dinosaur Park Formation and Horseshoe Canyon Formation. USA - Hell Creek Formation |
| Size: | 4.3 meters long, 1.4 meters high at the hip |
| Diet: | Uncertain but possibly an omnivore |
| Fossil(s): | Many individuals |
| Classification: | | Chordata | Reptilia | Dinosauria | Saurischia | Theropoda | Ornithomimidae | |
| Also known as: | | Ornithomimus altus | Ornithomimus sedens | |
Struthiomimus (meaning "ostrich mimic", from the Greek stroutheios/stroutheios meaning "of the ostrich" and mimos/mimos meaning "mimic" or "imitator") is a genus of ornithomimid dinosaurs from the late Cretaceous of North America. Ornithomimids were long-legged, bipedal, ostrich-like dinosaurs with toothless beaks. The type species, Struthiomimus altus, is one of the more common small dinosaurs found in Dinosaur Provincial Park; its abundance suggests that these animals were herbivores or omnivores rather than pure carnivores.