This paper describes a currently being developed procedure of the charged particle identification for CMD-3 detector, installed at the VEPP-2000 collider. The procedure is based on the application of the boosted decision trees classification method, and uses as input variables the specific energy losses of charged particles in the 14 layers of the liquid Xenon calorimeter. The performance of the procedure is demonstrated by an example of the extraction of events of e+e−→K+K−(γ) process in the center of mass energy range from 1.28 to 1.65 GeV. •The multilayer ionization calorimeter provides multiple dE/dx measurements.•The multiple dE/dx measurements can be used for particle identification.•The set of dE/dx values can be used as input of the boosted decision trees classifier.•The BDT response characterizes the likely type of the particle.•The approach works efficiently for kaon identification at momenta less than 1 GeV/c.