Black bruise in the wound after suture removal, may be bleeding around the knot, wound oozing and bruising. 1. During the process of wound closure, the thread knot passes through the small blood vessels, and after tying the knot, the local pressure stops the bleeding, and when the thread is removed, the thread knot is pulled out, which again damages to the small blood vessels, resulting in local bleeding and bruising, and black bruising is found in the wound. 2. It is also possible that the surgical wound hemostasis is not complete, the local continuous blood seepage, in the wound silt, the formation of bruises, after removing the suture, part of the bruises from the knot oozing. Black bruise is found, the amount of bruise is small and can be self-absorbed, while the amount is large and needs syringe suction and drainage. After removing the stitches, if there is black bruise in the wound, try to go to the hospital and let the doctor sterilize the wound to avoid long time bruise and infection.