The left anal opening seems to have a scraping sensation during bowel movement, which may be related to anal irritation, anal fissure, hemorrhoids, perianal abscess, polyps and other conditions. 1. Anal irritation: If the patient has recently been diarrhea, it may be due to repeated wiping of the anus and diarrhea, resulting in skin irritation at the anal opening, causing the discomfort of scraping. 2. Anal fissure: If the patient’s stool contains less water, the stool is too dry, when passing through the anus, the skin tissue around the anus will be torn, causing scraping pain. 3. Hemorrhoids: If the patient’s hemorrhoids are enlarged and red and swollen, when the stool is discharged, the stool repeatedly rubs against the hemorrhoids, resulting in significant discomfort in the hemorrhoids. 4. Perianal abscess: patients with perianal abscess will form an abscess in the anal area, there is obvious pain, in the stool, stool stimulation abscess, there will be discomfort. 5. Polyps: If the patient has polyps and the polyps increase in size, the passage of stool may become unsmooth, causing a scraping sensation. The left side of the anus seems to have a scraping sensation during the stool may also be other reasons, the patient should consult a doctor in a timely manner, a clear diagnosis, active treatment, so as not to delay the condition.