Nuristan province, in north-east Afghanistan, holds a significant portion of the country's remaining forests, but because of the inaccessible terrain and the recent history of poor security little is known about the wildlife inhabiting these forests. We conducted transect surveys in central Nuristan and confirmed the presence of musk deer Moschus cupreus > 60 years after the last documented observation of the species in Afghanistan. We found that, in summer, musk deer inhabit remote alpine scrub on scattered rock outcrops and in upper fringes of closed coniferous forests at c. 3,000–3,500 m. They invariably use steep slopes (≥ 20°), which makes them difficult to approach. We built a data-driven geographical model, which predicted that suitable habitat for musk deer in Afghanistan extends over c. 1,300 km2 in the contiguous provinces of Nuristan (75.5%), Kunar (14.4%) and Laghman (10.1%). Although relatively vast, the area of habitat potentially available to musk deer in Afghanistan appears to be highly fragmented. Despite indications of unsustainable hunting, this Endangered species persists in Afghanistan and targeted conservation programmes are required to protect it and its forest habitat.