Gums always bleed and bad breath may be caused by diseases such as periodontitis, gingivitis, caries, or other diseases such as wisdom teeth pericoronitis. 1. Periodontitis: Periodontitis is mainly due to microorganisms, host reaction and other factors, patients will have bleeding probing, brushing bleeding, periodontal abscess and other symptoms. In addition, patients with periodontitis will also have symptoms such as bad breath and root surface caries. 2. Gingivitis: most of the gingivitis is caused by localized plaque on the teeth, and the main symptoms of patients are bleeding when brushing teeth or biting hard objects, change of color of the gums, and soft and fragile gums, etc. In addition, patients with periodontitis may also have bad breath and root surface caries. In addition, gingivitis patients will also have pain, bad breath, itching and swelling and other symptoms. 3. Caries: Caries is mainly caused by a combination of factors such as bacteria, diet and time. The main symptoms of patients are a large number of food congestion and other symptoms, which will lead to the patient’s gums always bleeding and bad breath. 4. Other: Wisdom teeth pericoronitis, endodontitis and other diseases can also lead to the patient has always bleeding gums and bad breath performance. Patients with symptoms of bleeding gums and bad breath should go to the hospital in time and follow the doctor’s instructions for treatment.