The body mass of a male silvered leaf-monkey averages 6.6 kilograms and adult female averages 5.7 kilograms (Fleagle, 1999). Subadult males are about the size of adult females but smaller than fully grown adult males (Bernstein, 1968). The pelage color is a dark gray with the tips of the hairs being paler in color giving it a silvered effect. The groin and the ventral side of the tail are yellowish in coloration (Rowe, 1996). The face is black in coloration and the hair on the head is pointed (Furuya, 1961-2). Adult females have irregular patches of white on the inner portion of the upper thighs (Bernstein, 1968; Furuya, 1961-2). The newborn’s pelage color is orange, with the face, hands, and feet being white (Bernstein, 1968). Infants will darken and the darkening process takes 3-5 months to change to the adult pelage coloration (Bernstein, 1968; Medway, 1970). First the head starts to fade to a yellow orange, then the head, face, hands, feet, and ears turn dark gray and then black (Bernstein, 1968). This species has a sacculated stomach to assist in the breakdown of cellulose. The silvered leaf-monkey has enlarged salivary glands to assist it in breaking down food. The dental formula of this species is 2:1:2:3 on both the upper and lower jaws (Ankel-Simons, 2000).
The silvered leaf-monkey has a unimale social structure. The group is composed of a single adult male, several adult females, and immature individuals (Wolf and Fleagle, 1977). Males will live solitarily before finding a group of its own (Bennett and Davies, 1994). The groups are highly territorial and will act aggressively towards other individuals (Bernstein, 1968). Males will keep other group males out of the range of the group (Bernstein, 1968; Furuya, 1961-2). Conflicts will usually occur at the areas of home range overlap (Bernstein, 1968). Conflicts usually consist of chasing and/or fighting between the resident males (Bernstein, 1968). Adult males will move rapidly amongst the group and emit loud vocalizations when two neighboring groups come together (Bernstein, 1968). Other members of the group will squeal and embrace each other during group conflicts (Bernstein, 1968). Fighting consists of slapping and pulling with some biting (Bernstein, 1968). Intragroup agonistic behavior is rare in the silvered langur (Bernstein, 1968). Males disperse from their natal group. Infanticide has been reported to occur in this species (Wolf and Fleagle, 1977; Wolf, 1980). Infanticide results from an adult male coming into the group, killing the resident adult male, and killing the infants dependent on their mothers so that the adult females will begin to ovulate again (Wolf and Fleagle, 1977). An adult male that takes over a group will also chase out the immature males of the group (Wolf and Fleagle, 1977).
ku: This call is emitted by infants when they are in a peaceful state (Furuya, 1961-2). This call is also uttered by juveniles when addressing each other from a short distance (Furuya, 1961-2).
ho: This call is emitted by young males and females when addressing each other from a short distance (Furuya, 1961-2).
ku-ku: This call is uttered by adult females when greeting each other (Furuya, 1961-2).
kwah: This call is emitted by the adult male in order to control group travel movement (Bernstein, 1968). This call is emitted at repeated intervals (Bernstein, 1968).