Whether viruses or immunologic factors might cause or prevent human brain cancer is of interest. Statistically significant inverse associations of adult glioma with history of chickenpox and immunoglobulin G antibodies to varicella-zoster virus have been reported. The authors evaluate associations of immunoglobulin G antibodies to varicella-zoster virus and three other herpesviruses among 229 adults with glioma and 289 controls in the San Francisco Bay Area Adult Glioma Study (1997-2000). Cases were less likely than controls to report a history of chickenpox (for self-reported cases vs. controls: the age-, gender-, and ethnicity-adjusted odds ratio = 0.59, 95% confidence interval: 0.40, 0.86), and they also had lower levels of immunoglobulin G to varicella-zoster virus (for being in the highest quartile vs. the lowest quartile: the age-, gender-, and ethnicity-adjusted odds ratio = 0.41, 95% confidence interval: 0.24, 0.70). The inverse association with anti-varicella-zoster virus immunoglobulin G was most marked for glioblastoma multiforme cases versus controls and was only somewhat attenuated by excluding subjects taking high-dose steroids and other medications. Cases and controls did not differ notably for positivity to three other herpesviruses, Epstein-Barr virus, cytomegalovirus, and herpes simplex virus. Cohort studies may help to clarify the nature of the association between immunity to and/or clinical manifestations of varicella-zoster virus and glioblastoma.