Eating blood blisters in the mouth may be caused by bite wounds, improper diet, blood diseases and other factors. 1. Bite: Eating too fast or chewing improperly during meals may lead to teeth biting the oral mucosa, which will cause localized blood blisters, accompanied by obvious pain, or even rupture and bleed. 2. Improper diet: eating some hard food or too hot food, the mucous membrane in the mouth caused by irritation and damage, it will cause blood blisters. 3. Blood diseases: blood blisters in the mouth during meals may also be related to some blood diseases, such as thrombocytopenic purpura, aplastic anemia, which may be accompanied by pallor, fatigue and other symptoms. If the phenomenon of blood blisters in the mouth occurs frequently, and dietary factors and bite factors are excluded, it is recommended to consult a doctor for appropriate examination and treatment.