Trigeminal neuralgia (TN) occurred in 35 patients (1.9%) from a large multiple sclerosis (MS) clinic population (N = 1,882). TN began on average 11.8 years after the first MS symptom but in five patients was the first symptom of MS, preceding the next MS symptom by 1 to 11 years. The onset of MS was later in the patients who had TN, and bilateral TN occurred more frequently than expected (in 14% of TN patients). The age at onset of TN was no younger than in idiopathic TN except when TN was the first MS symptom. Most patients had a good result from medical or surgical therapy.