Bleeding gums when brushing teeth may be caused by incorrect brushing, gingivitis, periodontal disease, etc., which can be solved by adjusting the brushing method, scaling and surgical treatment. 1. Incorrect brushing: brushing too hard, using a toothbrush with too hard bristles and other reasons can lead to bleeding gums when brushing, you can keep the brushing force moderate, change the soft bristles of the toothbrush in a timely manner, and brush your teeth vertically with the upper and lower brushes. 2. Gingivitis: mostly caused by plaque infection, patients with gingivitis may have bleeding gums and swollen gums when brushing, you can remove plaque and tartar by scaling to improve the situation of bleeding gums when brushing. 3. Periodontal disease: plaque, tartar, food impaction and other reasons may lead to periodontal disease, the patient will appear red and swollen gums, bleeding gums, etc., you can remove calculus and plaque through supragingival scaling, subgingival curettage, and improve the bleeding gums by using saline local rinsing. Thrombocytopenia, leukemia and other blood system diseases can also lead to bleeding gums when brushing teeth, if the bleeding is serious and repeated should be timely to the hospital for clear diagnosis and treatment.