4-month-old babies often shake their heads while sleeping may be caused by environmental factors, eczema on the head, vitamin D or calcium deficiency and other factors. Parents should observe the baby in time to see if there are any other uncomfortable symptoms, and take the baby to the hospital for examination in time. First, environmental factors: due to the sleeping environment temperature is too high or too low, have poop, wet diapers are not changed in time, mosquito bites, etc., will lead to the baby can not sleep peacefully, head shaking, shaking and other symptoms. Parents need to carefully observe the baby’s sleeping environment for any abnormalities and try to help the baby adjust to the most comfortable state. Diligent to the child before going to bed to bathe, keep the skin clean, clean, so that the baby wearing loose, comfortable clothing to sleep, may allow the child to sleep more peacefully; Second, disease factors: 1, eczema on the head: the baby head eczema will cause scalp itching discomfort, will be manifested in the sleep of the old shaking head. Parents are advised to take their babies to the doctor in a timely manner, follow the doctor’s instructions for external boric acid solution, furacilin solution cold wet compresses, or apply zinc oxide paste, dexamethasone ointment; 2, Vitamin D or calcium deficiency: if the lack of vitamin D or calcium, the baby will appear at night sleep disturbances, crying, and often shaking his head. Parents should take the child to the hospital for examination, if rickets is diagnosed need to supplement calcium and vitamin D, let the child more sunshine, promote the absorption of calcium and vitamin D.