One year old baby scratching head itchy usually with itchy skin and other physiological factors and dermatitis, allergies and other pathological factors have a relationship. 1. Physiological factors itchy skin: a year-old baby scratching head itchy may be because the head sweat more or head clean unclean, resulting in head skin stimulation, itching. 2. dermatitis: seborrheic dermatitis or dermatitis caused by insect bites and other conditions can also make a one-year-old baby scratching head itchy situation. 3. Allergy: if a year old baby is allergic in the baby contact with clothes, pollen and other allergens may not only lead to the baby head itchy scratching head, usually accompanied by rashes and other symptoms. One year old baby scratching head itchy may also have other reasons, it is recommended to go to the hospital in a timely manner, improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.