The combination of cold and heat drug is a major feature of Zhang Zhongjing's clinical treatment. The author achieve good results in clinical practice by learning Zhang Zhongjing's treatment rules of combined use of cold and heat drug to cure diseases, and realize that the combined use of cold and heat drug belongs to the category of the combination’s treatment rule, and is a common treatment method for various diseases in clinic. The combined use of cold and heat drug has a special position in the treatment of spleen and stomach diseases. The key to the effectiveness of the combination of cold and heat drug is to weigh the partiality of cold and heat drug and grasp the proportion of cold and heat drug.