Abstract：There is no specific explanation of the connotation of “sevenfold reduction and eightfold boost” in Huangdi Neijing (The Yellow Emperor's Inner Classic) and physicians and scholars in past dynasties held different opinions. Starting from the connotation of “sevenfold reduction and eightfold boost”，the authors believe that it is the regular expression of changes of yin and yang and the human body. The nursing care of children lies in the prevention from diseases and promotion of growth and development. With focus on the law of changes of yin-yang of the four seasons and the human body as the key points， the application of theory of “sevenfold reduction and eightfold boost” to the nursing care of children attaches great importance to the effects of central function of the spleen and stomach and law of changes of five circuits and six qi on children.