Most of the species have white areas around the base of the tail and on the back of the thighs. The muzzle is normal and is neither expanded as in Pantholops nor elongated as in Saiga. The neck is not long as in Litocranius, and the back lacks the evertible folds present in Antidorcas. Both sexes of most species possess horns, which are smaller and more slender in females. One exception is G. subgutturosa, in which horns usually occur only in the males.
Many gazelles have lyre-shaped horns, but there is considerable variation among the species.
Gazelles usually occur in dry open country or brushland. The elevational range of the genus is sea level to 5,750 meters. In some areas there are large-scale seasonal migrations to different elevations or new feeding grounds. The populations of G. dama to the south of the Sahara move northward into the desert during the rainy season. This species, and some others, may form temporary aggregations of hundreds or thousands of individuals, but herd size is usually much smaller.