The Indonesian mountain weasel (Mustela lutreolina) is a species of weasel that lives on the islands of Java and Sumatra in Indonesia at elevations over 1,000 metres (3,280 ft). They live in mountainous, tropical, and rainforest areas. Indonesian mountain weasels have a body length of 11–12 inches and a tail length of 5–6 inches. They are reddish-brown in color. The Indonesian mountain weasel is endangered due to hunting, fur trade, and destruction of habitat. There are no subspecies of the Indonesian mountain weasel.