Abstract. Centrifugal compressors are an integral part of modern production in such industries as gas transmission, oil refining, metallurgical, machine-building, mining, as well as in electric and heat power engineering. Interruptions in the operation or failure of the compressor lead to decrease in profit or large material loss. Conditions should be created for the safe (stable) operation of the centrifugal compressor. Surge is global (complete) loss of stability, an unacceptable phenomenon for a centrifugal compressor. Compressor surge protection must function during operation. The algorithms used to protect the centrifugal compressor against surge have some drawbacks, which make it impossible to reliably exclude surge.There are many methods for analyzing rapidly changing processes in the flow part of a centrifugal compressor. The wavelet theory is the most accurate and modern method. The use of the wavelet transform method for signal processing allows us to solve the problems of analyzing non-stationary processes of a centrifugal compressor to expand the acceptable range of work and build reliable operation of the anti-surge diagnostic system. In the future, it is possible to use other basic wavelet functions, for comparison and selection of the most suitable one, for the analysis of unsteady signals in a centrifugal compressor.