The invention relates to a preparation method of a ZnO, CuO and ZnS quantum dot film. The preparation method comprises the following steps: preparing Cu ion modified ZnO quantum dot precipitate, CuO quantum dot precipitate and ZnS quantum dot precipitate; adding trichloromethane in the prepared quantum dot precipitates respectively to fully dissolve, then adding n-octylamine dispersant to obtain Cu ion modified ZnO colloidal quantum dot solution, CuO colloidal quantum dot solution and ZnS colloidal quantum dot solution; diluting the three kinds of colloidal quantum dot solutions with the sameamount of trichloromethane, filtering with a polytetrafluoroethylene (PTFE) filter, coating one or more of the colloidal quantum dot solutions on an indium-tin oxide (ITO) substrate through the spin-coating method, prebaking, and annealing in the air to obtain the quantum dot single-layer or multi-layer film. The preparation process of the invention is simple; the coated quantum dot film is compact and smooth and has good adhesion performance and controllable film thickness; and the quantum dot multi-layer structure is easy to realize and the quantum dot film is suitable for the multi-layer quantum dot film element.