The invention discloses a selenium butyric acid inclusion agent. The selenium butyric acid inclusion agent is based on the traditional Chinese medicines including ginseng, rubia cordifolia, fructus lycii, schisandra chinensis, coix seed, wolfiporia extensa, pseudostellaria heterophylla, selenium and the like, prepared by using a modern microorganism fermentation technology, processed by using a cyclodextrin inclusion technology, comprises histone deacetylase in a brand-new chemical structure to function as a pure natural synergistic inhibitor, comprises the composite compounds of selenium, butyric acid, flavonoid, saponin and the like, and belongs to the tumor epigenetic regulation medicine using the novel anti-tumor action mechanism; different from a traditional tumor treatment medicine, the selenium butyric acid inclusion agent carries out saturation attack by taking the abnormal epigenetic inheritance of the cancer cell as the target, exerts the whole anti-tumor effect by inducing the immune monitoring and immune killing actions of the patient, and is capable of resisting oxidation, appropriate in taste and free from chemical pollution.