A one and a half month old baby is fed on demand if breastfed, and the amount of milk is usually 90-150ml/time, every 3-4 hours if formula fed, but there are individual differences in infant feeding. The amount of milk a baby has has a lot to do with its own digestive function, stomach capacity, appetite or not, whether it is a premature baby and so on. One and a half months of the baby, the amount of milk is not fixed, every day to ensure that the amount of 500-600ml of milk to meet the basic needs of the baby’s growth and development, feeding the baby do not only consider these figures, according to the baby’s food to adjust the amount of milk, as long as the baby sleeps peacefully, normal urination and defecation, good mental state, do not cry and do not make a fuss, the weight is a trend of growth for a reasonable feeding. If the baby cries and is difficult to appease, it is recommended to go to the hospital in a timely manner to avoid delaying the condition.