The yellow baboon is a baboon in the family of Old World monkeys. The species epithet means "dog-head" in Greek, due to the dog-like shape of the muzzle and head. Yellow baboons have slim bodies with long arms and legs along with yellowish-brown hair. They resemble the chacma baboon, but are somewhat smaller and with a less elongated muzzle. Their hairless faces are black, framed with white sideburns. Males can grow to about 84 cm, females to about 60 cm. They have long tails which grow to be nearly as long as their bodies. The average life span of the yellow baboon in the wild is roughly 15–20 years; some may live up to 30 years.

Baboons are primates comprising the genus Papio, one of the 23 genera of Old World monkeys, in the family Cercopithecidae. There are six species of baboon: the hamadryas baboon, the Guinea baboon, the olive baboon, the yellow baboon, the Kinda baboon and the chacma baboon. Each species is native to one of six areas of Africa and the hamadryas baboon is also native to part of the Arabian Peninsula. Baboons are among the largest non-hominoid primates and have existed for at least two million years.