There is no standardized value for the length of an infant’s feet, only a reference value exists in the newborn period, not a standard value. Because of the individual variability of infants, the growth of foot length varies from month to month, therefore, the length of the feet cannot be used as a basis for judging the normal growth and development of infants. If the length of the hands and feet is obviously not consistent with the limbs, it can be seen as Marfan syndrome. For newborns, it is usually necessary to judge their intrauterine growth and development based on foot length, the average foot length of most male infants is 6.85-9.18cm, and the average foot length of female infants is 6.74-9.06cm, and most infants’ foot length (cm) = 1/6 body length (cm), and foot length (cm) = 1/2.5 upper limb length (cm), but this value and the way of calculation is only used as a reference value for most of the newborns. However, this value and the way it is calculated is only a reference value for the foot length of most newborns, not a standard value. If there is a large difference between the foot length of a newborn and the above values, but the growth and development of other parts of the body are normal, and there are no other diseases or uncomfortable symptoms, there is usually no need to worry too much. After the neonatal period, the difference between the growth of the infant’s feet and the growth of the infant’s feet is large, and the infant’s foot length alone cannot determine whether the infant is in a normal state of development, and at this time should also be based on the length of the infant, weight, sitting height, head circumference, chest circumference and so on, to comprehensively determine the growth and development of the infant.