In order to find out a fast, simple and accurate method to explore the types of mold growing on the surface of weapons and equipment after mold test, the mold test according to the standard test method is conducted in this paper. Fourier infrared spectrometer is used to test the samples corroded by different strains. Spectral data are obtained, and the identification region of spectral data is determined by principal component analysis. The minimum distance matching, spectral angle matching, spectral information divergence, spectral covariance, principal component analysis, PLS-DA and random forest are used to establish the recognition model. The results show that mold species can be identified well by the random forest algorithm, and the accuracy is expected to be more than 98%. Based on the appropriate classification algorithm, FTIR technology can realize the effective identification of bacterial species.