Blood blisters during cupping may be related to longer cupping time, more sensitive skin, improper operation and other reasons. 1. Cupping for a long time: In the process of cupping, due to the high temperature, if the cupping time is longer, it may cause certain stimulation to the skin, and there may be blood blisters in the process of cupping. 2. Sensitive skin: If the skin is sensitive, cupping can cause damage to the skin, which may also lead to the emergence of cupping blisters. 3. Improper operation: improper operation in the process of cupping, such as cupping in the thin part of the skin or the physician’s strength is too large, etc., may cause cupping blisters phenomenon. If cupping is needed, it is recommended to be operated by a professional physician. If the situation of blood blisters occurs, it is recommended that the patient go to the hospital in time and be operated by a professional doctor.