Rough skin on the back with granularity is firstly considered to be a symptom of keratosis pilaris, and may also be caused by skin allergies, skin amyloidosis, etc., which needs to be analyzed specifically. 1. Keratosis pilaris: this is caused by excessive keratinization of the hair follicle mouth, is an autosomal dominant disease, usually occurs in the patient’s extremities, back and even cheeks, the patient usually does not have obvious self-conscious symptoms, with the growth of the age of the symptoms of keratosis pilaris will be gradually alleviated. 2. Skin allergy: patients in contact with certain foods, drugs and other allergic substances, skin allergy symptoms may occur, manifested by skin roughness, accompanied by granularity, to avoid contact with allergens in a timely manner, anti-allergy treatment. 3. Skin amyloidosis: If the skin on the back has a granular roughness, it may be skin amyloidosis, which refers to amyloid deposition in normal skin without involving other organs, a chronic skin disease, accompanied by obvious itching. Back skin roughness with granularity may also be a symptom of folliculitis and other diseases, it is recommended to go to the hospital in a timely manner, improve the examination for symptomatic treatment.