Symptomatic early neurosyphilis is a rare manifestation of syphilis that usually occurs within the first 12 months of infection. Most neurologic symptoms of early neurosyphilis result from acute or subacute meningitis, abnormalities in cranial nerve function, and inflammatory vasculitis leading to a cerebrovascular accident. Symptomatic early neurosyphilis essentially disappeared in the United States after the introduction of penicillin treatment for syphilis in the late 1940s but reappeared in the 1980s among persons with human immunodeficiency virus (HIV) infection. The disease burden from neurosyphilis is unknown because national reporting of this disease is incomplete. Because the increase in syphilis cases during the past 5 years has occurred primarily among MSM, many of whom were infected with HIV, CDC conducted a review of possible neurosyphilis cases to describe the clinical course of symptomatic early neurosyphilis and to better characterize the risk for this illness among HIV-infected MSM. The review included health department records from four U.S. cities (Los Angeles, California; San Diego, California; Chicago, Illinois; and New York, New York) for the period January 2002-June 2004. This report describes the results of that review, which identified 49 HIV-positive MSM with symptomatic early neurosyphilis during that 30-month period. Among HIV-positive MSM with early syphilis, the estimated risk for having symptomatic early neurosyphilis was 1.7%, and the risk for having early neurosyphilis with persistent symptoms 6 months after treatment was 0.5%. These findings emphasize the importance of preventing syphilis in HIV-infected persons. HIV-infected persons with cranial nerve dysfunction or other unexplained neurologic symptoms should be evaluated for early neurosyphilis.