Professor LI Naigeng has been engaged in pediatrics formore than 50 years, and has accumulated rich experience in the process of syndrome differentiation and treatmentof children′s spleen and stomach diseases. Nowadays, children often prefer meat to vegetarianism. Professor LIbelieves that eating toomuch meat, fishy and greasy food can easily damage Yin, especially spleen and stomach Yin deficiency. Overeatingmeat, sweet food and fried food are easy to produce gastrointestinal heat stasis and other diseases. In the treatment of children′s spleen and stomach diseases, drugs are based on eliminating pathogenic factors, and dredgingmethod and eliminatingmethod are commonly used. Eliminatingmedicine is good at using Ezhu (zedoary turmeric) and Dahuang (rhubarb) in order to dredge the bowels andmake the evil have away out. Professor LIchose to use Dahuang (rhubarb) according to the efficacy of different processed products, and Dahuang (rhubarb) was divided into three different doses: large, me-dium and small doses. Dahuang (rhubarb) ismainly used for attack in large doses, and tonic in small doses. Professor LIbelieves that all kinds of infantilemalnutrition syndrome are caused by spleen and stomach diseases, and so the treatment is to invigorate the spleen and stomach, and take care of the spleen and stomach during diet. Professor LIis good at treating children′s spleen and stomach diseaseswith external therapy, themethod is simple and the effect is obvious. Professor LI believes that children often suffer from deficiency of Qi and Yin. The causes include blowing air conditioning, eating cold drinks, overeating fat and sweet food, and abusing antibiotics and hormones. Professor LIis good atusing "protecting Yang and benefiting Yin" to treat spleen and stomach diseases in children. This paper summarized Professor LI Naigeng′s clinical experience in the treatment of children′s spleen and stomach diseases, and analyzed Professor LINaigeng′s academic thoughts of "protecting Yang and benefiting Yin" and "gastrointestinal blood stasis and heat theory". One case of typicalmedical cases was attached.