Large-scale laboratory researches of autoclave oxidation of sulphide gold-bearing concentrates at one of the deposits of the Amur Region have been realized. The results of semi-industrial tests of autoclave oxidation with different correlation of liquid phase to hard phase have been presented. The chemism of pyrite and arsenopyrite oxidation during autoclave leaching has been described. The results of large-scale laboratorial researches show that technology of flotation beneficiation — autoclave oxidation — sorption cyanidation is usable for processing of sulphide gold-bearing material from this deposit in the Amur region and allows to obtain throughout recovery of gold not less than 78 %.