They have striking rust-red fur, with black to gray legs and a white stripe down the spine. They have white and black facial markings and white rings around their eyes. They are the most colorful pigs and they use their colors, ear tassels, and neck manes in spectacular threat displays. Their snout is elongated with two well-developed warts in older males. The fur on the jaw and the flanks is longer than on the body. They are sexually dimorphic (2 distinct gender forms). The male is slightly larger than the female and has recognizable ridges on both sides of the snout. Both genders have smaller upper tusks and lower tusks that can reach up to 3 inches.

This African pig thrives in the forest, where it forages for many kinds of food, often leaving areas stripped of standing plants. They are nocturnal (active at night) and rest by day in a self-dug burrow. They live in family groups called "sounders" usually consisting of 4 to 6 pigs led by a dominant male. Large sounders may have up to 20 pigs, consisting of several adults and young of various ages. Although not normally aggressive, they actively defend their young. If threatened, they may attack people or other animals. With their substantial weight and large tusks, they can be formidable fighters. They mark their paths by scraping tree trunks with their tusks as well as scent marking with foot glands, neck glands and preorbital glands. Red river hogs fight by pressing their foreheads together, butting heads, jabbing with their snouts, and whipping each other with their tails. They are fast runners and good swimmers.