White-faced sakis exhibit marked sexual dimorphism. Males have black fur and a white face, while females have brown or grayish tones, with two lighter vertical lines running from the eyes to the nose.

Diurnal and arboreal, they use their long, bushy tail to maintain balance when jumping from one tree to another, but it is not prehensile.

They live in small groups of two to four individuals, although larger groups of six or more have been recorded, which may include more than one breeding adult male or female. They are monogamous, especially in captivity and in large groups.

To establish their territory, they emit loud vocal calls, which male and female pairs often perform in duets, thus reinforcing their courtship bond. To socialize, they often groom each other.

They reach sexual maturity at approximately 2-3 years of age, although this is generally earlier in females. The mother is responsible for caring for her young, who remain attached to her thigh until they are one month old. Afterwards, they move to the mother's back to facilitate mobility.

Hunting and habitat loss are its main threats.