They have long, reddish-gold fur with a mane that covers their ears and frames their dark, almost bare faces. Their long toes and claw-like nails help them cling to trees and forage among branches, bark, and bromeliads to feed and catch prey. They are monogamous and form territorial groups of 2 to 11 individuals, led by a mate. They defend their area with scent markings and vocalized threats. This marmoset grooms itself like other primates, with males primarily grooming females. They can reproduce twice a year. During the first week of life, the female carries the young, but later the males also do so, and parenting duties are shared by the group. The young are weaned after 3 months.

Given its endangered status, primarily due to habitat destruction, several reintroduction programs have been implemented through various zoological institutions. Coordinated by the National Zoological Park, Washington, DC, the golden lion tamarin program is a successful model for captive breeding and reintroduction. Thanks to the efforts and collaboration of various zoos between 1984 and 2000, the number increased to approximately 3700 in 2014. The reintroduction program also resulted in an 80% increase in available habitat for this species. One of the main threats currently facing this callitrichid is yellow fever, which has resulted in a population reduction of at least 30%. in situ enjoyed between 2014 and 2019.