5-month-old baby shaking his head can be physiological, there may also be pathological factors (calcium deficiency, head and face eczema). 1. Physiological factors: 5 months began to be curious about the outside world, shaking their heads to express excitement, happy emotions. At the same time, the imitation of 5-month-old babies is gradually improving. It is also possible to imitate the head shaking movement of adults. 2.. Pathological factors: (1) Calcium deficiency: Calcium deficiency will cause the baby’s nerve excitability to increase, thus the symptoms of head shaking. (2) eczema on the head and face: eczema on the head and face can cause itching and other discomforts, causing the baby to shake his head. 5 months baby shaking head, there may be other reasons, it is recommended to go to the hospital in time to improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.