Spit up in the morning with blood but not pain is considered to be the emergence of oral ulcers, gingivitis periodontitis, gastritis and other diseases. 1. oral ulcers, some patients with oral ulcers oral mucosal damage may lead to capillary rupture, so there will be up in the morning spit blood but no pain symptoms. 2. Gingivitis periodontitis, patients with gingivitis, swelling around the gums, increased sensitivity, blood flow, may lead to capillary rupture, this symptom. 3. Gastritis, patients with gastritis due to gastric erosion may bleed, so it will produce the morning spit up with blood but not painful symptoms. However, blood in the morning spit may also be caused by other reasons, if this symptom often occurs, it is recommended to consult a doctor in time for examination and treatment.