Four wapiti (Cervus canadensis) from Oklahoma which had shown clinical signs of neurologic disease were submitted for pathological examination. Both mature female and larval meningeal worms (Parelaphostrongylus tenuis Pryadko and Boev, 1971) were either observed in or recovered from the meninges and parenchyma of the brains. Lesions found in the brain of each wapiti included focal meningitis, perivascular cuffing, and focal gliosis; frequently these were associated with the meningeal worms. There appeared to be a direct correlation between the presence of meningeal worms and lesions observed histologically which resulted in neurologic disturbances in the wapiti.