Blood blisters on the neck of an 80-year-old man may be related to trauma, or may be caused by herpes zoster, allergic vasculitis and other causes. 1. trauma: 80-year-old man if the neck area accidentally by accidental cuts, resulting in local trauma, resulting in local skin tissue oozing, may appear in the neck blood blisters, may also be accompanied by local swelling, bruising and other manifestations. 2. Herpes zoster: the disease is usually due to varicella zoster virus infection, typical lesions for the ganglion along the band-shaped distribution of erythema, blisters, when the lesions involved in the deeper, blood blisters, blisters, preferred in the back of the chest and head, face, neck. 3. allergic vasculitis: the disease is mainly due to bacterial and viral infections, which can make the patient’s capillaries, micro-veins or micro-arteries and other small blood vessels rupture, necrosis, thus triggering inflammatory diseases, when the inflammatory reaction is more serious, it will lead to local subcutaneous tissue hemorrhagic reaction, which may result in the neck of the blood blisters. 80-year-old man with blood blisters on the neck, may also be caused by other reasons, it is recommended to seek medical attention as soon as possible, to give targeted treatment and conditioning.