Bilateral trigeminal neuralgia is uncommon and usually occurs in 1% to 11% of patients with trigeminal neuralgia. There has been no report of a patient with bilateral trigeminal neuralgia in Korea. Based on our review, the incidence of bilateral trigeminal neuralgia among the trigeminal neuralgia patients who visited our pain clinic numbered 0.7% (4 out of 531). This is much lower than those of other previous studies. This lower incidence might be explained by the fact that we excluded those patients with mild bilateral trigeminal neuralgia which did not require treatment and also patients whose symptom on controlateral side was relieved by injection of local anesthetics for that side. Among the four patients with bilateral trigeminal neuralgia, three patients received alcohol block of the branches of trigeminal nerve and one refused the treatment. Overall, three patients maintained good or excellent pain relief without any serious complications throughout the follow-up period.