Cancer and increased age are risk factors for coagulation activation. Patients with advanced prostate cancer, which usually presents in the seventh to eighth decade of life, are likely to be at increased risk for thrombosis. We report results of a controlled study of changes in specific and sensitive markers of coagulation activation in patients with prostate cancer. Complete blood count, prothrombin time, partial thromboplastin time, prothrombin fragment 1 + 2 (F1 + 2), thrombin–antithrombin complex (TAT) and quantitative D-dimers (DD) were measured in 30 patients of advanced prostate cancer (androgen ablated), in 30 newly diagnosed localized prostate cancer patients, in 30 healthy age-matched volunteers, and in 20 healthy young volunteers. Plasma F1 + 2 (P< 0.05) and DD (P< 0.05), but not TAT, were significantly elevated in healthy elderly males (mean age, 77 years) when compared with healthy young volunteers (mean age, 35 years). F1 + 2, TAT and DD were significantly elevated in advanced prostate cancer when compared with healthy age-matched controls (P< 0.001). In conclusion, advanced prostate cancer patients have significantly increased levels of sensitive markers of coagulation activation compared with healthy age-matched controls. This data can be used to plan studies to determine the risk of clinically significant coagulopathy and the role of primary prophylaxis in patients with advanced prostate cancer.