A patient with symptomatic trigeminal autonomic cephalalgia (TAC) provides a chance to understand the pathophysiology and anatomic correlates of TAC. A 28-year-old woman experienced intermittent sharp and excruciating pain over her right temporal, ear and neck regions for 3 days. The headaches lasted 10-20 minutes each, occurred 1-2 times a day, and were accompanied by prominent ipsilateral lacrimation and conjunctival injection. The patient had hiccups, 4-limb numbness and impaired visual acuity in both eyes. She had also had 3 episodes of left-side optic neuritis in the past half year. Neurologic examination showed brushing allodynia over the right face and scalp during the headache attacks. The visual acuity of her right eye was 6/60 and that of the left eye was 1/60. Brain magnetic resonance imaging showed non-enhancing lesions on the right lateral tegmentum of the lower pons where the spinal trigeminal nucleus is located and the floor of the 4th ventricle. The patient was diagnosed as having multiple sclerosis with symptomatic TAC. Her headaches, autonomic signs and allodynia subsided 3 days after pulse therapy and gabapentin treatment were given. We suggest that the spinal trigeminal nucleus lesion was responsible for the symptomatology of TAC and cutaneous allodynia in our patient.