Patients appearing like goose bumps on arms and legs may be caused by perifollicular keratosis, sweat pore keratosis, atopic dermatitis and other causes. 1. Perifollicular keratosis: Perifollicular keratosis is a chronic follicular keratosis skin disease, the main clinical manifestations of the follicle mouth keratin plugs, keratinized papules, accompanied by varying degrees of perifollicular erythema, the skin is a “chicken skin”-like appearance, the majority of patients usually do not have self-conscious symptoms, a small number of patients may experience a slight itching sensation. 2. Keratosis pilaris: Keratosis pilaris is a rare chronic hereditary keratosis abnormalities, mostly caused by autosomal dominant inheritance, the main typical performance of the sweat pore around the edge of the dyke-like raised pimples or plaques, the performance of the “chicken skin”-like appearance. 3. Allergic dermatitis: a class of skin diseases caused by allergen stimulation, mainly including eczema, urticaria, drug rash, etc., the patient may appear erythema, pimples, blisters, masses and other lesions, accompanied by a sense of itching and other symptoms, the patient’s arms and legs like goose bumps may be caused by allergic dermatitis. It is recommended that patients seek medical examination in a timely manner to clarify the cause of the targeted treatment, pay attention to monitoring the condition in life, regular review.