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A review is presented of experiments performed using the KEDR detector at the VEPP-4M accelerator complex for the precise measurement of particle masses. The resonant depolarization method, proposed in 1975 at the G I Budker Institute of Nuclear Physics of the RAS Siberian Branch for measuring beam energy, has undergone further development in the experiments described; an unprecedented accuracy of $ 5\times 10^{-7}$ has been achieved. Application of this method together with measurement of the Compton backscattering energy allowed a series of experiments to be carried out which have provided the world's most accurate mass values for the $ {\rm J}/{\rm\psi}$, $ \rm {\psi(2S)}$, $ \rm {\psi(3770)}$, and $ {\rm D}^{\pm }$ mesons for the $ \rm {\tau}$-lepton.

A review is presented of experiments performed using the KEDR detector at the VEPP-4M accelerator complex for the precise measurement of particle masses. The resonant depolarization method, proposed in 1975 at the G I Budker Institute of Nuclear Physics of the RAS Siberian Branch for measuring beam energy, has undergone further development in the experiments described; an unprecedented accuracy of has been achieved. Application of this method together with measurement of the Compton backscattering energy allowed a series of experiments to be carried out which have provided the world's most accurate mass values for the , and mesons and for the -lepton.