Winter goosebumps on the legs, can be seen in physiological factors, may also be related to keratosis pilaris. 1. Physiological factors: when the weather is cold, the erector spinae muscle is stimulated to contract, which can cause goose bumps. 2. Keratosis pilaris: the cause is related to heredity and other factors, which is a chronic follicular keratosis pilaris skin disease. Keratosis pilaris is typically manifested by small papules on the skin surface, lesions are generally normal skin color can also be presented as reddish, surface roughness, the appearance of chicken skin-like changes. The lesions are usually worse in winter and less severe in summer. The treatment of keratosis pilaris has obvious individual differences, and is generally symptomatic, such as the use of topical retinoic acid ointment, urea cream, etc., and the appropriate use of some moisturizers to alleviate the excessive dryness of the skin. Keratosis pilaris is a chronic disease, and medication must be used in accordance with the doctor’s instructions during treatment.