The Department of Anorectal Medicine recently admitted three consecutive patients with similar bleeding manifestations in the stool, which were eventually clarified by colonoscopy as internal hemorrhoids, colon tumors and rare colonic diverticulosis. All three patients had bright red color and large amount of blood in the stool, and there was no obvious anal pain when bleeding, no obvious hemorrhoid bulge outside the anus was viewed, and no obvious bleeding spots were seen under the anoscope. Because the bleeding was fresh and not obviously mixed with stool, the location of bleeding was considered to be low, mostly in the distal colon, and the common causes were mostly internal hemorrhoids, ulcerative colorectitis, and tumors. In the past five years, an 84-year-old woman had recurrent blood in her stool, accompanied by abdominal pain and dyspareunia, and was found to have a malignant tumor 15 cm from the anus, which broke and bled and caused incomplete obstruction, followed by abdominal pain and dyspareunia; another 45-year-old middle-aged man had bleeding in his stool for the past three days, which came out in drops and stopped after the stool. Another 58-year-old patient was watching TV at home 3 hours before admission, and suddenly he wanted to relieve his stool, and the interval was several minutes, and he relieved his stool 4 times, the volume was more, mainly blood, and the colonoscopy was performed for congenital intestinal dysplasia, multiple diverticula, infection rupture and bleeding, this kind of patients are very easy to intestinal perforation and secondary peritonitis. Three patients, whose condition was finally determined, were treated accordingly. Yang Baohua, Department of Anorectal Medicine, Puyang Central Hospital Some patients with blood in stool have extremely similar clinical symptoms. As a doctor, you should master the key points of differential diagnosis of suspected cases, remove the falsehoods and keep the truth to avoid misdiagnosis and omission; as a patient, due to the lack of professional medical knowledge, you must be cautious and careful and seek timely medical consultation to avoid delaying the condition and losing the best time for treatment.