Abstract：Objective：To explore the differences between ancient and modern ideas of reinforcing yang by exploring and studying the medication rules in Huai Xuan Yi Xue Quan Shu (Huaixuan Medical Encyclopedia)， extracting and analyzing the clinical ideas of Huaixuan Medical School， and by comparing with the theories of Yang-Reinforcing Medical School. Methods：The prescriptions and medicinals involved in Huai Xuan Yi Xue Quan Shu were sorted out and extracted， and the medicinals meeting the inclusion criteria were statistically analyzed and a database was established. SPSS Statistics 24.0 and SPSS Modeler 18.0 were used to specifically analyze the medicinal frequency， natures， flavors， channel entry， medication dosage，association rules and clustering. Results：A total of 386 prescriptions were screened， involving 327 kinds of medicinals. The medicinals used were mainly warm in nature and sweet in flavor，and mainly entered the spleen channel， which showed strong concentration. The correlation analysis showed that the key was based on the combination of medicinals for the spleen and the stomach of the middle energizer， and 15 medicinal pairs were formed； clustering analysis showed that there were 6 new prescriptions； and it was found that the dose of Zingiberis Rhizoma， Cinnamomi Cortex and Aconiti Lateralis Radix Praeparata tended to be cautiously decided according to medication dosage analysis. Conclusion： Huaixuan Medical School is characterized by warming and supplementing， who attaches importance to supplementing and boosting both the postnatal and the prenatal spleen and stomach. It also focuses on regulating the pivot movement of the spleen and the stomach and harmonizing yin and yang. It has formed a series of characteristic theories and methods， which have a profound influence on Yang- Reinforcing Medical School，but they also have great differences from them.