The red-cheeked chinchilla is a medium-sized chinchilla with a body length of up to 258 mm, slightly smaller than the long-tailed chinchilla. The tail is very short, and its length is 13-24.1% of the body length, with an average of 17.3%. The hind paws are bare, only the proximal metatarsals are covered with short hairs.

The back of the red-cheeked squirrel is a color of sand from the top of the head to the base of the tail Yellow, or one color gray-yellow, mixed with gray-black tones. Some of the forehead area is brownish-yellow. Body back with yellow-white ripples, or no ripples. The tip of the nose, the upper edge of the eyes, the upper front of the ears, and the cheeks have brownish-yellow or rust stains.