The patient was a 61-year old male on maintenance dialysis who underwent transrectal prostate biopsy due to a high PSA level. The patient started suffering from intense pain in the anal region 1 hour after the biopsy, and in 7 hours, intense lower abdominal pain and bilious vomiting developed. Progressive anemia was observed with a giant retroperitoneal hematoma which had partially extended intraperitoneally on a non-contrast CT image. These findings might have been caused by arterial bleeding which occurred during the prostate biopsy. The general condition was stable, and the symptoms were improved by blood transfusion and conservative treatments.