Hyopsodus is a genus of extinct early ungulate mammal of the family Hyopsodontidae, a group associated with or basal to the Perissodactyla.

The exact number and identity of species has been contested, as is common when taxa are erected based on fragmentary materials.

However, there is broad agreement that multiple species in the genus lived in the Wasatchian, Uintan, and Bridgerian North American Land Mammal Ages, and they have been used both to reconstruct paleoenvironments and to study evolutionary change.

They show Hyopsodus individuals had an arched back with a posture similar to a hyrax, rather than a weasel-like tube-shaped body.

[5] In their heyday, Hyopsodus species may have occupied a variety of niches later taken by other flexible forest feeders such as rats, small early perissodactyls, and hypocarnivores like raccoons.