Blood in stool with dark red color can be considered as rectal cancer, ulcerative colitis, bacterial dysentery, peptic ulcer and other diseases. 1. Rectal cancer develops for a period of time will form localized erosion and blood seepage in the intestinal tract, which will later be discharged together with feces. Since the blood stays in the intestinal tract for a period of time, it is discharged with feces in dark red color. 2. Due to the stimulation of inflammation, patients with ulcerative colitis will have intestinal blood seepage, and then the blood in the intestines will turn into dark red color and follow the feces, so the patients will also have the manifestation of dark red blood in the stool. 3. When bacterial infection occurs in the intestines, such as dysentery bacillus, etc., the intestinal mucosa will have blood seepage, and at this time, the patient will also be accompanied by abdominal pain, abdominal distension, feces with blood, and the color is dark red. 4. Peptic ulcer will often have excessive secretion of gastric acid, resulting in gastrointestinal bleeding, the blood through the intestines will become dark red with the feces. If you have dark red stool bleeding, please consult a doctor in time to clarify your condition and give you appropriate treatment.