The invention relates to a preparation method of copper-based water-resistant catalyst M-Cu/SiO2 and a use method. Firstly, 0.1 mol/L of a copper nitrate solution containing doped metal is prepared, acheap carrier acidic silica sol is dropwise added, a certain amount of ammonia solution is added for reaction, the residual solution is subjected to hydro-thermal treatment, washing, alcohol washingand drying are performed, finally roasting is performed to obtain a catalyst M-Cu/SiO2. A doping method is utilized to modify a Cu/SiO2 catalyst. It is proved through XRD and N2O titration that all metal species are evenly distributed on the carrier silicon, HRTEM and XRD show that the doping of the M metal leads to the formation of lattice defects of the catalyst, which can be used as the activesite of the reaction. The catalyst is used in the hydrogenation of ethyl acetate containing impurities, has higher catalytic activity, ethanol selectivity and stability at low temperature and has a wide application prospect in the fields such as chemical engineering.