Objective To study the dynamic changes of human milk components in different periods in order to guide the rational feeding to the baby. Methods One hundred and twenty one health mothers were surveyed.The contents of protein,fat,carbohydrate,energy and dry matters in their milk before and after feeding were determined by MIRIS human milk analyzer. Results The contents of protein in milk in 1^st~3^rd months after delivery were significantly higher than other months.The change of fat and energy in milk was consistent.The fat and energy in the milk before feeding were no difference in different months.The fat and energy in the milk after feeding in the tenth and twelfth months were significantly higher than those of other months.The contents of protein in milk before and after feeding in the first month after delivery were no obvious difference,and they were higher in the milk before feeding than those in the milk after feeding in other months.The contents of fat and dry matters and energy were significantly higher in the milk after feeding than those in the milk before feeding in each period,while the contents of carbohydrate were higher in the milk before feeding than those in the milk after feeding in each period. Conclusion Human milk has its own changes in different periods of postpartum.