  The paper describes a method of the charged particle identification,
developed for the \mbox{CMD-3} detector, installed at the VEPP-2000
$e^{+}e^{-}$ collider. The method is based on the application of the boosted
decision trees classifiers, trained for the optimal separation of electrons,
muons, pions and kaons in the momentum range from 100 to $1200~{\rm MeV}/c$.
The input variables for the classifiers are linear combinations of the energy
depositions of charged particles in 12 layers of the liquid xenon calorimeter
of the \mbox{CMD-3}. The event samples for training of the classifiers are
taken from the simulation. Various issues of the detector response tuning in
simulation and calibration of the calorimeter strip channels are considered.
Application of the method is illustrated by the examples of separation of the
$e^+e^-(\gamma)$ and $\pi^+\pi^-(\gamma)$ final states and of selection of the
$K^+K^-$ final state at high energies.
