Objective of the study was to demonstrate practicability of data base creation, containing reference mass-spectra of agents of particularly dangerous infections, using MALDI-TOF mass-spectrometry, by the example of plague agent strains. Materials and methods. MALDI-TOF mass-spectrometry was deployed for the obtainment of mass-spectra of ribosomal proteins from the microorganisms under investigation with the help of mass-spectrometers - Microflex LT. Results and conclusions. Carried out was comparative analysis of the obtained mass-spectra of 10 Y. pestis strains and reference spectra of Y. tuberculosis , contained in commercial data base of MALDI Biotyper 3.1 (Bruker Daltonics, Germany). Developed data base was validated in the process of identification of plague microbe strains, isolated in the territory of natural plague foci of the Russian Federation. That data base provided for correct identification of Y. pestis strains up to a species.