The itch behind the ear is firstly considered whether it is because usually no attention is paid to the cleanliness behind the ear, resulting in the accumulation of a large amount of dust or sweat secretions in the sulcus behind the ear and the symptoms of itch behind the ear, so attention should be paid to one’s own hygiene. When mosquitoes bite the skin behind the ear, itching and local redness behind the ear will also occur. This situation can be relieved by applying glycopyrrolate lotion or glucocorticoid topical preparations such as mometasone furoate cream. In addition to the above, itching behind the ear may also occur if the patient suffers from frostbite, otitis externa, or eczema of the external ear. 1. Frostbite: the thin skin of the ear, lacking subcutaneous fat protection, can lead to vasoconstriction and ischemia and hypoxia in the ear in a cold environment thus forming frostbite, manifesting as redness and swelling, and itching when exposed to heat. 2. Otitis externa: the patient’s skin in the outer ear and behind the ear has become inflamed due to infection. Inflammation of the skin behind the ear due to infection, and the inflammation factor stimulates the skin, causing itching behind the ear; 3. Eczema of the external auditory canal: Eczema of the skin behind the ear due to various internal and external factors, which causes skin inflammation, manifesting as itching, local erythema and exudation behind the ear.