Microcebus ravelobensis is the largest of the western Madagascar mouse lemurs. It has a head-body length of 12–13 cm, a tail length of 15–17 cm, a total length of 27–30 cm, and a body weight of 56–87 g (Rasoloarison et al., 2000; Andriantompohavana et al., 2006). The dorsal coat, including the crown and ears, is rufous and mottled; the mid-dorsal stripe is poorly defined. The lighter ventral fur is also mottled or bicolored. The region between the eyes is pale grayish, changing to cinnamon toward the crown. Tail color darkens toward the tip (Zimmermann et al., 1997, 1998).
Microcebus ravelobensis is sympatric with M. murinus, and can be confused with it in the wild. However, Microcebus ravelobensis has a longer tail and is rufous in coloration.