Normal baby’s muscle tone is usually accompanied by a lifetime, will not disappear, the human body has a normal muscle tone, in order to maintain the posture and normal movement. The muscle tone of a normal baby changes every month after birth and gradually decreases after three months. As long as there are no obvious abnormal symptoms and the baby develops normally, parents need not worry too much. Babies may have high muscle tone in the first three months, because the first month after birth, the baby’s body is generally in flexion mode, in the passive activities of the limbs will produce some resistance, so there is a mild case of high muscle tone, generally after three months, muscle tone will gradually reduce. If after three months there is still hypertonia, the baby’s limbs still move more rigidly, indicating that there may be damage to the central nervous system, parents are advised to take the baby to the hospital in a timely manner. When the baby’s muscle tone is pathologically altered due to the influence of disease, the muscle tension will appear too high or too low. When the muscle tone is too high, the movement of the baby’s limbs or trunk will become stiff, which may be caused by central lesions and damage to the corticospinal tract. When the muscle tone is low, the limb or trunk movement becomes soft, which may be caused by a genetic metabolic disease or a muscular lesion. Pathological changes in muscle tone do not usually disappear on their own. If parents find that their baby’s muscle tone is significantly abnormal, they need to take their baby to the child health department for a joint mobility assessment and diagnosis by a doctor to identify the specific cause and treat the cause. The recovery time varies depending on the cause of the disease and the physical condition of the individual. At home, parents can help their babies with rehabilitation exercises such as passive exercises, swimming or hydrotherapy to help relieve abnormal muscle tone.