The brown-eared woolly opossum is characterized by a brown to reddish brown coat and similarly colored limbs, yellow to orange underbelly, hairless, brown ears with a hint of pink, and a tail furred up to half of its length dorsally (on the back) and up to 20% of its length at the base. The coat may be tinged with gray, and develops a shade of orange on the shoulders, limbs and the
crown; young are typically grayer. The fur is fairly long, soft and thick. The tail becomes less bushy towards the tip, leaving the last 30% of the length bare. This naked part is typically white with a yellowish tinge, and spotted with brown. Faint orange rings circle the eyes on the grayish white face. A dark stripe runs up the nose and between the eyes up to the back of the ears. The subspecies may vary in coloration;
C. l. circur is largely grayish brown, while
C. l. lanatus is a pale brown and does not show spots on the tail. The head-and-body length is between , and the tail is long. The opossum weighs . Hindfeet measure , and the ears measure . The
dental formula is – typical of didelphids. The brown-eared opossum differs from the
bare-tailed woolly opossum in having a bushier tail (in the bare-tailed opossum, the tail turns bare abruptly after the first one-third of the length) and a pouch that opens to the front rather than along the midline.
Derby's woolly opossum differs from the brown-eared opossum in having white limbs and gray fur between the shoulders. The brown-eared opossum differs from other opossums in having a comparatively large
braincase. ==Distribution and status==