Abstract： To summarize and analyze the relationship between constrained fire of the spleen and the stomach and the antithesis， and to guide clinical diagnosis and treatment based on this. According to the analysis， it is believed that constrained fire of the spleen and the stomach comes from the fact that the antithesis is out of coordination and yin qi and yang qi are out of place and cannot go back to its original place，resulting in the disorder of ascending and descending of the qi movement of the spleen and the stomach. In the mechanism of the application of the theory of antithesis in differentiating and treating constrained fire of the spleen and the stomach，if the antithesis is coordinated and the heart and the kidney interact， the spleen and the stomach can make their qi ascend and descend. Therefore， in the treatment of constrained fire of the spleen and the stomach，it is better to use unblocking and guiding method and to regulate the ascending and descending of qi movement；the essence of the treatment is related to the exterior，unblocking of the center and the restoring of interaction between the heart and the kidney.