We analyzed the expression level and cellular localization of pro- and anti-inflammatory cytokines and histopathologically characterized canine traumatic brain injury (TBI). Canine TBI brains revealed subarachnoid and cerebral cortical hemorrhage, neutrophilic infiltration, neuronal necrosis, astrocytosis, and vasogenic edema. Immunohistochemical evaluations suggested that both pro-inflammatory cytokines [interleukin (IL)-1β, IL-6, and tumor necrosis factor-α] and anti-inflammatory cytokines [IL-10 and transforming growth factor-beta (TGF-β)] were highly expressed in neurons and neutrophils. In particular, the highest magnitude of expression was identified for IL-1β and TGF-β. This data helps describe the pathologic characteristics of canine TBI, and may help in the design of potential therapeutic approaches to control secondary damage by inflammatory cytokines.