Spread of tumor to cavernous sinus is an infrequent and late manifestation of head and neck cancers. Perineural spread occurs along the trigeminal nerve to eventually involve the cavernous sinus. Initially, patients with cavernous sinus involvement along the trigeminal nerve have facial dysesthesias to be diagnosed as trigeminal neuralgia mistakenly. If intracranial foramina have not been transgressed, surgery and radiotherapy have been curative. Otherwise treatment is largely palliative. Early recognition and diagnosis are very important because cavernous sinus involvement has a poor prognosis. We report a case of transitional cell carcinoma of the maxillary sinus involving the cavernous sinus along the maxillary division(V-2) of trigeminal nerve by perineural spreading, which is presented with facial pain and confirmed by computerized tomography and magnetic resonance imaging.