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We applied near infrared spectroscopy (NIRS) to feces collected from free-ranging mule deer (Odocoileus hemionus) on the western Kaibab Plateau, north of the Grand Canyon, to evaluate its applicability as a management tool. This historically and ecologically significant deer herd annually moves along an elevational gradient; wintering in the Western North Kaibab Woodland at ~1800m asl and spending summers in the Kaibab Plateau Forestland at ~2400m asl. Predominant woodland species include Utah juniper (Juniperus osteosperma), Gamble oak (Quercus gambelii), cliffrose (Purshia mexicana) and big sagebrush (Artemisia tridentata). Ponderosa pine (Pinus ponderosa), Aspen (Populus tremuloides), and mixed conifer dominate the higher elevation forest with an understory that includes grasses such as blue grama (Bouteloua gracilis) and squirreltail (Elymus elymoides) with forbs such as yarrow (Achillea millefolium) and cinquefoil (Potentilla spp.). Winter diet is considered to be the limiting factor for this herd. Many techniques to acquire nutritional information on herbivores require invasive techniques or close observation. Fecal pellet groups contain information about deer diets. We collected fecal pellets during March to September in 2012 and January to September in 2013. Diet crude protein (CP) and digestible organic matter (DOM) as well as fecal nitrogen (N) and phosphorus (P) were predicted with NIRS calibrations developed using white-tailed deer (Odocoileus virginianus), elk (Cervus elaphus), domestic sheep (Ovis aries) and domestic goats (Capra hircus). Year and month affected diet quality (P < 0.05). NIRS-predicted diet CP and DOM varied greatly between calibrations. Mahalonobis distance (H) values indicated that these mule deer samples were not closely related to the existing elk, deer or domestic animal calibrations (i.e. all > 10.0). Samples from this herd should be added, however, H values from multi-species fecal N calibrations were 4.5 ± 0.5, indicating that this calibration can be used to evaluate fecal N in west Kaibab mule deer.