The article discusses vibration diagnostics methods for assessing the technical condition of the spindle assembly of metal-cutting machines and
determining its dynamic characteristics. The technical condition of the spindle assembly is important in determining defects that have arisen in its mechanical system. In particular, this paper describes a method for analyzing the singularity parameters of deep groove ball bearings, the spectral distribution of driving forces, and analyzing the system dynamics using the Fourier transform. A technique based on determining the frequency spectrum of system oscillations and identifying defects is presented.