Stabbing pain near the anus when it gets wet may be related to perianal trauma, anal fissure, hemorrhoids and other causes. 1. Perianal trauma: when the patient’s perianal area has been traumatized, such as contusion, cuts, puncture wounds, etc., due to the obvious traumatic surfaces localized in the perianal area, the traumatized surfaces may become irritated after getting wet, resulting in a stinging sensation. 2. Anal fissure: is the dentate line below the anal canal skin layer cracked after the formation of small ulcers, when the patient’s anal area after getting wet, may stimulate the ulcer surface of the local nerve endings, resulting in a tingling sensation, and some patients may also appear constipation, blood in the stool and other symptoms. 3. hemorrhoids: hemorrhoids is a common anal disease, due to the lower end of the anorectal canal rectal venous plexus congestion, swelling caused by hemorrhoids patients in defecation resulting in hemorrhoidal friction damaged, may cause stinging pain after contact with water. In addition, after perianal surgery may also cause such a situation, it is recommended that patients seek medical examination in a timely manner to clarify the cause of the targeted treatment, so as not to delay the condition.