Trigeminal neuralgia is paroxysmal lancinating pain that causes a considerable discomfort and a marked reduction in the quality of life. The pathogenesis may be due to vascular compression of the trigeminal nerve at the root entry zone, posterior fossa tumor and multiple sclerosis. The compression of maxillary nerve by deep belly of temporalis muscle have not been studied. The authors report the case of a 69-year-old Chilean woman with typical right trigeminal neuralgia at the maxillary branch who was referred for palliative anesthetic blocks. Neuroradiological examinations were used to discard vascular compression or presence of lesion in the central nervous system. The images showed the presence of the deep portion of the temporalis muscle with its supero-medial insertion in a close relationship with the emergency of the maxillary nerve and infraorbital nerve at the roof of pterigopalatine fossa. Trigeminal neuralgia occurs due to focal demyelination of the trigeminal nerve. This is a rare case reporting a typical trigeminal neuralgia in a patient where all possible causes have been previously ruled out. We found a close relationship with deep belly of temporalis muscle (DBTM) and maxillary nerve, at its supero- medial insertion. The patient was treated by BTX-A applied at DBTM. Our findings, based on the literature review, point out the importance of such anatomical condition when dealing with patients affected by cranial nerve dysfunction syndrome.