The invention relates to the cell disruption of microbes and the preparation of the microbe proteins for mass spectrometric analysis. The cells of microbes from microcolonies are disrupted by physical or chemical means directly on the nutrient medium. The released proteins are then transferred to sample supports by direct contact with their contact surfaces; electrophoresis can be used for assistance. Once the the proteins are firmly adsorbed on the contact surfaces, they can be washed with water in order to remove substances which interfere with the ionization process. For analysis by matrix-assisted laser desorption (MALDI), the proteins are prepared on the contact surfaces of the sample supports with matrix substances to form MALDI samples; the sample supports are then introduced into a MALDI mass spectrometer for the acquisition of the mass spectra. The microbes are identified by similarity comparisons between the mass spectra of the microbe proteins and similarly obtained reference spectra.