A method for preparing a multilayer-color composite material for use in dental department comprises: preparing multiple types of monochromatic composite material precursor powder different in color, carrying out dry-pressing and preforming on the precursor powder, so as to obtain a preformed green body; and then carrying out pressurization and heating processing on the preformed green body, so as to obtain a multilayer-color composite material that gradually changes in color from neck portions to incisal ends of teeth, so that the multilayer-color composite material has a higher similarity to the material of natural teeth.