The invention discloses a preparation method of a microreactor containing an immobilized catalyst and belongs to the field of wall-immobilized microreactors containing catalysts. According to the method, an COF (covalent organic framework) material is adjusted and grown in situ by adding controlling agents to the inner wall of the microreactor to be served as a supported catalyst carrier. The microreactor has the characteristics of being high in catalysis efficiency, capable of preventing leakage of the catalyst, improving the stability of the catalyst and the like.