Northern flying squirrels (Glaucomys sabrinus) of the Black Hills National Forest (BHNF) of South Dakota represent a unique and isolated population, but little is known about the distribution and habitat use of this population. A resource selection function (RSF) habitat model was created for northern flying squirrels (G. sabrinus) throughout BHNF. Using methods from Manly et al. (2002) and Johnson et al. (2006), logistic regression was used to compare habitat variables at used habitat locations (radio-tracking and trapping locations) to a random sample of available habitat locations throughout the study area. Logistic regression coefficient estimates of significant variables were incorporated into a GIS raster layer to produce a map with RSF values for BHNF. The RSF values were transformed to a relative probability of habitat use ranging from 0 to 1. Independent validation data were used to determine model fit based on predictive performance of the RSF. Data used in the model determined that northern flying squirrels in BHNF used habitats with higher precipitation, closer distance to a stream, aspen (Populus tremuloides), northwest aspect, higher basal area of snags and a higher density of live trees and snags than randomly available habitats. The RSF map identifies possible high use areas of habitat by northern flying squirrels throughout BHNF and is useful for management purposes, as well as a baseline for future research and monitoring for an isolated population at the southern edge of their range.