Itchy skin when exposed to the sun is mainly due to polymorphic solar rash, which can be dealt with by physical sun protection and medication. Polymorphic solar rash is due to sun-induced delayed hypersensitivity reaction, resulting in skin damage, itching, can be accompanied by erythema, papules. Sun exposure should be avoided and protection should be taken. When you go out, you can protect yourself from the sun by using physical means such as umbrellas, wide-brimmed hats, and long-sleeved clothes. When itching occurs, topical medication can be used to stop itching with glycerite lotion, or topical 3% boric acid lotion. If the symptoms are severe, oral chloroquine, niacinamide, hydroxychloroquine sulfate can be taken to relieve the symptoms. When the skin itches more seriously when the sun is exposed to the sun, you should consult a doctor in a timely manner to clarify the cause of the disease and follow the doctor’s instructions for treatment, do not self-medication.