Hydrometallurgical investigations of gold antimony flotation concentrate have been carried out. XRD and chemical analyses of the concentrate have been studied. Mainly, the material consists of compounds of antimony, silicon, calcium, sulfur and iron. The main phases are quartz, stibnite, calcium carbonate and ankerite, pyrite and arsenopyrite have been found as well. The feature of antimonite’s dissolving in alkaline solutions has been reviewed. The dependences of effects of the temperature, time, L/S ratio and NaOH concentration on the extraction antimony and sulfur from the flotation concentrate have been determined. During sulphide-alkaline leaching of the starting material several physicochemical characteristics of gold dissolution has been identified.