The Altai birch mouse has a yellowish back, cream-colored underside, brown ears, and a two-toned tail. Its original description was based on one specimen from the Altai Mountains.
The type specimen had a yellowish back finely mixed with brown and a cream-colored underside. Its ears were brown, and its tail was brown above and gray below.
That specimen was collected in a thicket within a rainy mountain forest with nut pines. The original account provides no further observations of its behavior or diet.
An extinction-risk assessment has not been added yet.