Suddenly a black blood blister on the tongue may be related to the mechanical stimulation in the oral cavity, lack of trace elements, etc., should be based on different reasons for the corresponding treatment, can choose medication or local treatment and other methods. 1. Mechanical stimulation in the oral cavity: the sharp edges of the residual roots and crowns of the teeth repeatedly stimulate the mucous membrane of the tongue, causing capillary rupture and the symptom of black blood blisters on the tongue. Such patients should seek timely medical treatment, under the guidance of the doctor to remove the teeth that cause irritation. At the same time, attention should be paid to oral hygiene, conducive to recovery. 2. Lack of trace elements: Due to the lack of trace elements such as zinc, iron, vitamin B12, etc., the symptoms of black blood blisters on the tongue can also occur. Such patients can be treated with oral vitamin B12, zinc gluconate oral solution, ferrous succinate and so on. It can also be supplemented by eating foods rich in zinc and iron, such as egg yolks, oysters, animal livers, black beans, etc. 3. Local treatment: the blood bubble is small, no special treatment, can let it self-absorption, if the blood bubble is large, can seek medical treatment, with a syringe to draw out the blood in the blood bubble, need to pay attention to oral hygiene, to avoid infection. Patients with a black blood blister on the tongue are advised to go to the hospital in time for consultation, to clarify the cause of the disease, and then take reasonable medication and standardized treatment according to the doctor’s guidance.