The fontanelle is divided into the fontanelle and the posterior fontanelle. Under physiological conditions, the fontanelle closes at about 18 months of age and the posterior fontanelle closes at about 3 months of age. Under pathological conditions, some infants may experience early closure of fontanelle 5-6 months after birth, which can cause microcephaly and affect the infant’s intellectual development. If the infant’s fontanelle does not close late in the first 18 months of life, it is common for the infant to be dehydrated and should be hydrated in a timely manner. If the infant’s fontanelle bulges and is accompanied by fever, vomiting or even convulsions, it indicates that the infant’s intracranial pressure is elevated and should be seen by the pediatrician in a timely manner. In addition, during the period of fontanel closure, infants need to eat a diet based on high-quality protein, and they need to take appropriate amounts of calcium and vitamin D supplements, and insist on outdoor activities and moderate exposure to sunlight to promote the absorption of calcium.