The Pontic-Caspian steppe is the vast steppeland stretching from the north of the Black Sea (Graeco-Roman tradition refers to it as the 'Hospitable sea', Euxeinos Pontos (Εὔξεινος Πόντος) - thus a euphemism - in antiquity) as far as the east of the Caspian Sea, from western Ukraine across the Southern Federal District and the Volga Federal District of Russia to western Kazakhstan, forming part of the larger Eurasian steppe, adjacent to the Kazakh steppe to the east. It is of the paleartic temperate grasslands, savannas, and shrublands ecoregion of the temperate grasslands, savannas, and shrublands biome.

The area corresponds to Scythia and Sarmatia of Classical antiquity. Across several millennia the steppe was used by numerous tribes of nomadic horsemen, many of which went on to conquer lands in the settled regions of Europe and in western and southern Asia. It was finally brought under the control of a sedentary people by the Russian Empire in the 16th to 18th centuries.

The term Ponto-Caspian region is used in biogeography for plants and animals of these steppes, and animals from the Black, Caspian and Azov seas. Genetic research has identified this region as the most probable place where horses were first domesticated.