The goal of this study was to investigate the associations between ovarian cancer risk and usual consumption of black tea, regular coffee, or decaffeinated coffee. Using a hospital-based case-control design, participants included 414 women with primary epithelial ovarian, fallopian, or peritoneal cancer and 868 age- and region-matched women with nonneoplastic conditions. All participants completed a comprehensive epidemiologic questionnaire. Black tea consumption was associated with a linear decline in ovarian cancer risk (P for trend 0.03), with individuals consuming two or more cups daily experiencing a 30% decline in risk (adjusted OR 0.70, 95% CI 0.51-0.97). Similar declines were noted among individuals consuming two or more cups of decaffeinated coffee daily (adjusted OR 0.71, 95% CI 0.51-0.99; P for trend 0.002). However, no association was noted between any level of regular coffee consumption and risk of ovarian cancer. The chemoprotective effects of phytochemicals in black tea and decaffeinated coffee may be important, although the effects of phytochemicals in regular coffee may be counteracted by the elevated risk associated with its higher caffeine content.