The invention relates to a mimic enzyme prepared from a metal copper complex and a preparation method thereof. A molecule expression of the mimic enzyme is CuO@SiO2-NH2-FA. The preparation method for the mimic enzyme comprises the following steps: (1) synthesizing a complex 1) -[Cu(L)(CH3COOH)]n; (2) calcining the complex 1), thus obtaining a calcined oxidation product; (3) modifying and representing the oxidation product: 1) preparation of CuO@SiO2; 2) preparation of CuO@SiO2-NH2; 3) activation with folic acid and 4) preparation of CuO@SiO2-NH2-FA. The mimic enzyme provided by the invention is obtained by modifying the calcined product of the complex; the mimic enzyme prepared according to a chemical method is high in stability, convenient in storage and low in cost; according to the invention, the complex is represented, the modification and representation of the calcined product are researched, the mimic enzyme is further applied to the enzymatic research, and lastly, an experiment research proves that the acquired modified product has a hydrogen peroxide mimic enzymatic property.