Topics in equine medicine related to the temporomandibular joint (TMJ) receive far less attention than other branches such as lameness, infectious disease and reproduction. Problems with the TMJ can affect a horse’s ability to chew and properly digest its food and to perform as an athlete. The anatomy of the equine dentition is such that the constructs of the teeth highly influence the overall motion of the mandible and the grinding capacity during the chewing cycle. Consequently, regular dental exams and treatments are essential to the overall health of the animal. As in most branches of medicine, it is important to first understand normal function prior to analyzing pathologies. This study examines the normal chewing pattern of seven horses while chewing two different feed types:​ hay and pellets. Retro-reflective spherical markers were adhered to the horse’s skull and mandible and a Motion Analysis System recorded the marker locations as the horses chewed hay and pellets. The data were processed with customized software and the three-dimensional displacement and rotations, described as pitch, roll, and yaw, of the mandible relative to the skull were computed. In addition, a virtual tracking marker was created on the mandible and tracked relative to the skull. The mandible was found to have a significantly greater range of motion while chewing hay versus pellets. The mandibular velocity while chewing hay versus pellets was not significantly different.