An inhabitant of dense rainforest. In Taï N. P., frequently observed in wetland areas including swamp forest (poor drainage areas dominated by prop-root trees and raffia palms) and riverine habitat (Dunham and Gaubert 2013). However, one specimen collected in a region of moist woodlands and savanna in Guinea makes its restriction to rainforest questionable (Gaubert et al. 2002). In addition, a recent record by Pacheco et al. (2013) further supports the hypothesis that Johnston's Genet may inhabit certain forest–savanna mosaics.

Largely restricted to the forests of the Upper Guinea rainforest block, having been long recorded from Guinea, Sierra Leone, Liberia, Côte d’Ivoire, and Ghana (Gaubert et al. 2002, Dunham and Gaubert 2013). Recently, Pacheco et al. (2013) presented the first record of Johnston's Genet in Senegal, through a camera-trap video recorded in April 2011 in Dindefelo Natural Reserve, south-eastern Senegal, about 260 km north of the species's westernmost previous known occurrence.

Although present in several protected areas, several of these require improved protection because hunting is intense even within them, such as Mt Nimba, Ziama Classified Forest and Taï N. P. Further survey work is necessary to determine whether secondary growth and moist woodland areas provide suitable habitat for this species (Dunham and Gaubert 2013).