Horsfield's Tarsier (Tarsius bancanus) is a small body, big round eye, and nocturnal animal. There was lack of people knowledge regarding the number of species, biological aspects, usability, and its conservation. The research aimed to calculate population density of Horsfield's Tarsier. Data was collected in line transect. The population density of Horsfield's Tarsier in the Area of Rampah Menjangan Waterfall was 7,84 individual/km² indicating that the status of this tarsier was scarce.