Producing of heterogeneous concentrates with good recovery in the processing of polymetallic ores is a challenge. Many factors must be taken into account including ore grinding, reagent mode, water composition, pulp density and the volume of supplied bubbles when producing high-quality selective concentrates. Microbubbles smaller than 50 μm in size were produced based on the frother oxal T-92 at different concentrations using a generator. The most optimal number of microbubbles smaller than 50 µm was produced at a T-92 concentration of 0.5 g/dm3. Polymetallic ore of Kazakhstan deposit was used for flotation studies. The studies were conducted in the copper-lead rough concentrate producing cycle. Flotation active minerals chalcopyrite and galena pass into the foam product, while sphalerite and pyrite remain in the chamber product in this cycle. In this paper, the density of pulp (20, 30 and 50%) as one of the main factors that effects the selectivity of flotation is studied. The kinetics of ore flotation in the base mode and with the use of a microbubble generator has been studied at these densities. Test experiments have been performed at the optimum density. The use of a water–air microemulsion generator makes it possible to maintain the quality of the copper-lead concentrate and increase the extraction of copper into the rough concentrate by 7.41%, lead by 5.98%.