Chicken skin is also known as keratosis pilaris and is considered to be related to genetic inheritance. Keratosis pilaris usually appears congenitally, and it is less common to develop chicken skin suddenly. Possible causes such as sun exposure and other factors. 1. Sun exposure: On the basis of genetic defects, if the skin is exposed to ultraviolet rays for a long time, it may lead to skin damage. The skin’s ability to repair itself decreases, inducing keratosis pilaris. 2. Other factors: exposure to radiation, vitamin deficiency, long-term exposure to lithium carbonate and other factors may lead to recurrence of perifollicular keratosis. Keratosis pilaris also has an obvious seasonality, the symptoms are relieved in winter and may further aggravate in summer. If the patient feels itching, pain or abnormal skin lesions, it is recommended to consult a doctor and receive treatment as soon as possible.