Bleeding of prostatic origin is usually caused by the friable hypervascularity of the prostate, the vessels of which are easily disrupted by physical activity. The condition is often ignored after the patient has been fully investigated and more serious causes for bleeding excluded and treatment is often withheld unless the bleeding becomes excessive. We analysed the clinical effect of finasteride in the treatment of this condition. We retrospectively reviewed 42 patients diagnosed as having haematuria secondary to bleeding from a benign prostate. Eighteen patients were simply reassured and given no treatment. Twenty-four patients with prostatic bleeding were treated using finasteride. All case notes were reviewed and the patients were contacted by telephone. Of 18 patients who had prostatic bleeding but did not receive treatment the mean age was 70 y and the mean follow-up was 10 months; two had died, nine had no further bleeding, two had a single episode of bleeding requiring no treatment, six had several bleeding episodes of whom one started finasteride, one refused treatment, and three required TURP. In the group treated with finasteride the mean follow up was 9 months, the mean age of the patients was 75 y. Twenty patients had no further bleeding, one patient experienced minor intermittent bleed and required no further treatment. Two patients died of non-urological causes, one patient stopped the treatment because of impotence and one patient had mild gynecomastia. Haematuria secondary to prostatic bleeding can be significant if not treated. Finasteride appears to be effective in suppressing haematuria caused by benign prostatic hyperplasia and should be considered in treating this problem.