Black blood blisters on the tongue are usually not AIDS. Patients should first address the tongue trauma where the blood blisters appear, perform blood tests, and then pathology tests. Most of the black blood blisters on the tongue are due to tongue trauma caused by the tongue mucosa being cut by teeth or hard objects, resulting in black blood blisters on the tongue surface. In some patients with bleeding disorders, blood blisters may easily appear after tongue trauma; cancer of the tongue may develop white spots or cauliflower-like changes with unclear borders and roughness to the touch, and may appear as black blood blisters at a later stage. In contrast, the appearance of black blood blisters on the tongue is generally not directly related to AIDS. Patients with AIDS may develop multiple infections due to severe impairment of immune function, and may have white or gray-brown tongue coating and large, deep ulcers in the oral cavity on the tongue, but generally do not develop black blood blisters. If patients find black blood blisters on the tongue, they should not pick them by themselves to avoid infection. It is recommended to visit the stomatology department of a regular hospital in time to clarify the cause and then carry out symptomatic treatment.