The gums are a part of the oral mucosa with rich vascular distribution, which itself is a part that bleeds easily. Bleeding gums indicate the presence of inflammation in the gums and periodontium, and in a few cases, gum bleeding is caused by coagulation dysfunction due to systemic diseases, so it needs to be taken seriously. Gum bleeding is mainly caused by local factors and systemic original factors. Local factors and inflammation of the gums, trauma, etc. cause bleeding. This kind is easy to recognize in life and can be seen in the gums with some swelling, injury and other manifestations. For example, the stimulation of long-term soft tartar, tartar, and food embedding can cause chronic inflammation of the gums, which causes the blood vessels to dilate and bleed; in addition, it is common to have trauma to the gums, such as the poking of meat and bones, fish spines, and damage to the blood vessels of the gums by brushing or toothpicks, which can also cause bleeding. Systemic factors and disruption of the coagulation mechanism in the body, thus causing bleeding. The coagulation and dissolution of blood in the body is a state of equilibrium, and when suffering from some diseases, this equilibrium is broken and bleeding is easy, and the gums are the most frequent place for bleeding. Examples include having leukemia, thrombocytopenic purpura, granulocyte deficiency, hemophilia, pernicious anemia and scurvy, or taking oral aspirin tablets for a long time. The causes of bleeding gums are complex, especially if the bleeding is due to systemic factors, and it is important to seek prompt medical attention to find out the cause in order to treat the problem properly.