Several case-control studies have suggested that nonsteroidal anti-inflammatory drugs (NSAIDs) reduce risk for glioblastoma, an aggressive form of brain cancer. Prospective investigations have not observed such an association, but these studies lacked adequate brain cancer case numbers and did not stratify by histologic subtype. We prospectively investigated the association between NSAID use and risk of all glioma as well as the risk of glioblastoma subtype in the National Institutes of Health (NIH)-AARP Diet and Health Study. The frequency of aspirin and nonaspirin NSAID use 1 year prior to baseline was ascertained using a self-administered questionnaire. Hazard ratios (HRs) and 95% confidence intervals (CI) were estimated using Cox regression models with age as the underlying time metric, adjusted for sex, race, and history of heart disease. The analysis included 302,767 individuals, with 341 incident glioma cases (264 glioblastoma). No association was observed between regular use (>2 times/wk) of aspirin and risk of glioma (HR = 1.16; 95% CI, 0.87-1.56) or glioblastoma (HR = 1.17; 95% CI, 0.83-1.64) as compared with no use. Null associations were also observed for nonaspirin NSAID use (HR for glioma = 0.90; 95% CI, 0.65-1.25 and HR for glioblastoma = 0.83; 95% CI, 0.56-1.20) as compared with no use. Our findings from this large prospective study do not support an inverse association between NSAIDs and risk of all glioma or glioblastoma.