The guenons (/ɡəˈnoʊn/ or /ˈɡwɛnən/) are the genus Cercopithecus of Old World monkeys.
All members of the genus are live in sub-Saharan Africa, and most are forest monkeys. Many of the species have small ranges, and some have local subspecies. Many are threatened or endangered because of habitat loss.
The species now put in the genus Chlorocebus, such as vervet monkeys and green monkeys, used to be species in this genus, Cercopithecus aethiops.