Sudden congestion and blackening of the uvula, consider submucosal bruising, may be related to dietary stimulation, vomiting and other stimuli, may also be related to inflammatory diseases of the throat. 1. Dietary stimulation, vomiting and other stimuli: if the diet is too spicy, too hot, or drinking alcohol, vomiting and other stimuli, may cause submucosal hemorrhage and bruising of the uvula. If there is no sore throat, foreign body sensation, fever and other symptoms, it is recommended to gargle more, keep the mouth clean, most of the bruises can be slowly absorbed. 2. Inflammatory diseases of the throat: including acute pharyngitis, tonsillitis and other conditions, may be related to viral infection or bacterial infection. Need active anti-infection symptomatic treatment. At the same time, it is recommended to improve the blood routine, coagulation function examination, to check whether there is a possibility of blood system diseases. It is recommended that the patient go to a regular hospital in time, under the guidance of the doctor to actively treat the cause.