This paper describes the clinical presentation and diagnosis of a peripheral nerve sheath tumor in the caudal cervical spine of a dog. A nine year old mixed breed dog presented to the Cornell University Hospital for Animal’s Neurology Service for evaluation of ataxia and weakness that had progressed over the months prior to presentation. The dog was eventually diagnosed with a peripheral nerve sheath tumor. Magnetic resonance imaging was utilized to initially identify the mass. Final diagnosis was achieved through necropsy and histopathology. The report illustrates the use of physical exam, imaging, anatomic pathology, and histopathology to make a diagnosis of peripheral nerve sheath tumor in the caudal cervical vertebral canal.