Homotherium is an extinct genus of machairodontine saber-toothed cats, often termed scimitar-toothed cats, that ranged from North America, South America, Eurasia, and Africa during the Pliocene and Pleistocene epochs (5 mya–10,000 years ago), existing for approximately 5 million years.

It first became extinct in Africa some 1.5 million years ago. In Eurasia it survived until about 30,000 years ago. In South America it is only known from a few remains in the northern region (Venezuela), from the mid-Pleistocene. The last scimitar cat could have survived in North America until 10,000 years ago.