Colobinae is a subfamily of the Old World monkey family that includes 58 species in 10 genera, including the skunk-like black-and-white colobus, the large-nosed Proboscis Monkey, and the gray langurs, sacred to India. Some classifications split the colobine monkeys into two tribes, while others split them into three groups. Both classifications put the two African genera Colobus and Piliocolobus in one group, both genera distinct in that they have a stub thumb. The various Asian genera are placed into one or two other groups. Analysis of mtDNA confirms that the Asian species form two distinct groups, one of which contains langurs, with the "odd-nosed" species in the other, but suggests that the gray langurs are not too closely related to either.

Colobines are medium sized primates with long tails and diverse colorations. It is remarkable that nearly all of the young animals differ in their coloring substantially from the adults.

Most species are arboreal, although some live a more terrestrial life. They are found in many different habitats of the different climate zones (rain forests, mangroves, mountain forests and savanah), but not in deserts and other dry areas. They live in groups, but in different group forms.

They are almost exclusively herbivores, which predominantly nourish themselves on leaves, flowers and fruits. They occasionally eat insects and other small animals. To aid in digestion, particularly for hard to digest leaves, they have a multipart, complex stomach. Unlike the other subfamily of Old World monkeys, the Cercopithecinae, they possess no cheek pouches.

Gestation averages six to seven month. Young are weaned for approximately one year and are mature at 3 to 6 years. Their life expectancy is approximately 20 years.