There are several potential causes of a bleeding mouth, and it is important to see a dentist or doctor for a proper diagnosis and treatment plan. Some possible causes of a bleeding mouth include gum disease, gingivitis, or periodontitis, which are all conditions that affect the gums and can cause them to bleed. Other possible causes include a mouth injury, such as a cut or bite, or an underlying medical condition, such as blood disorders or vitamin deficiencies. In some cases, a bleeding mouth can be a sign of a more serious condition, such as oral cancer. It is important to see a dentist or doctor if you have a bleeding mouth, as they can provide a proper diagnosis and treatment plan.