If the coagulation function is abnormal or the number of platelets is significantly lower, it will lead to blood leakage from the capillaries in the body, resulting in bruising; timely treatment must be given to avoid bleeding that is difficult to stop. Secondly, it may be that the blood vessel wall in the patient’s body is fragile, and a slight trauma may lead to the rupture of the blood vessels under the skin, or even the sudden force of the patient may lead to the rupture of the blood vessels in the body, thus causing the bruise to appear on the patient’s body; it is recommended to go to the hospital for a detailed examination, and after a clear diagnosis, it is recommended to actively treat the symptoms.