The invention belongs to the technical field of medicine, and discloses fusidic acid chemically modified compounds, and a preparation method and an application thereof. The fusidic acid chemically modified compounds have a structure represented by a formula 1. In the formula 1, R1 and R2 are hydrogen atom, halogen, alkoxy, trifluoromethyl or alkyl. According to the invention, a natural product, namely fusidic acid, is subjected to chemical modification, such that a series of fusidic acid derivatives are obtained. The method has the advantages of simple preparation method and high synthesis yield. The obtained fusidic acid is chemically modified, and the chemically modified fusidic acid can be widely applied. Pharmacological experiments show that part of the fusidic acid chemically modified derivatives have a significant effect in inhibiting bacterial (such as Wolbach phage) activity, which means the type of compounds can be applied in preparing medicines used for preventing, controlling or treating bacterial infections. The compounds can also be used as additives for preparing medical instruments with sterilization and disinfection functions.