Method for the surface treatment of a stainless steel workpiece, characterized in that it comprises at least the following steps: - shot peening/shot blasting of at least one surface of said workpiece, wherein there are used shots/beads made of electrocast austenitic stainless steel, respectively stainless steel obtained from metal wire, and which are essentially spherical, respectively cylindrical, with a diameter of the spherical body, respectively of the cross section of the cylindrical body, substantially from around 0.4 to 0.8 mm; said method being implemented in an automatic turbine system with inverter, which controls the continuous variation of the rotation speed of the turbine motor and therefore the blasting speed of the shot/beads, so that on said at least one surface of said workpiece there is provided a surface micro-roughness, having micro-peaks and micro-valleys that reduce the area of contact of the worked surface, and - electro-polishing of said at least one surface of the workpiece by means of tank with an galvanic bath with electrolytic cell, wherein said tank, made of an electroconductive material, comprises a first inner coating made of insulating plastic material and a second inner coating made of stainless steel, superimposed on the said first coating and electrically connected to cathode means of the electrolytic cell, with formation of a corresponding electrical field extended to the total surface of said second inner coating, and in that guides made of a good electrically conductive material are applied to the two opposite edges of said tank and are electrically connected with respect to said second coating and to the corresponding cathode means of the electrolytic cell, while support bars with respective sliding blocks made of a good electrically conductive material are engaged, in electrical contact and sliding, along said guides, and are electrically connected with at least two steel plates, at least partially immersed in the galvanic bath, forming moving cathodes and arranged on opposite sides with respect to the workpiece, which is supported fixed in said galvanic bath and electrically connected with respect to the anode means of the electrolytic cell, and which is maintained during the galvanic treatment at a distance variable from around 100 to 150 mm with respect to the said moving cathode means, so that said surface microroughness is reduced, lowering and rounding by removal of material of said micro-peaks of the surface of the workpiece. - shot peening/shot blasting of at least one surface of said workpiece, wherein there are used shots/beads made of electrocast austenitic stainless steel, respectively stainless steel obtained from metal wire, and which are essentially spherical, respectively cylindrical, with a diameter of the spherical body, respectively of the cross section of the cylindrical body, substantially from around 0.4 to 0.8 mm; said method being implemented in an automatic turbine system with inverter, which controls the continuous variation of the rotation speed of the turbine motor and therefore the blasting speed of the shot/beads, so that on said at least one surface of said workpiece there is provided a surface micro-roughness, having micro-peaks and micro-valleys that reduce the area of contact of the worked surface, and - electro-polishing of said at least one surface of the workpiece by means of tank with an galvanic bath with electrolytic cell, wherein said tank, made of an electroconductive material, comprises a first inner coating made of insulating plastic material and a second inner coating made of stainless steel, superimposed on the said first coating and electrically connected to cathode means of the electrolytic cell, with formation of a corresponding electrical field extended to the total surface of said second inner coating, and in that guides made of a good electrically conductive material are applied to the two opposite edges of said tank and are electrically connected with respect to said second coating and to the corresponding cathode means of the electrolytic cell, while support bars with respective sliding blocks made of a good electrically conductive material are engaged, in electrical contact and sliding, along said guides, and are electrically connected with at least two steel plates, at least partially immersed in the galvanic bath, forming moving cathodes and arranged on opposite sides with respect to the workpiece, which is supported fixed in said galvanic bath and electrically connected with respect to the anode means of the electrolytic cell, and which is maintained during the galvanic treatment at a distance variable from around 100 to 150 mm with respect to the said moving cathode means, so that said surface microroughness is reduced, lowering and rounding by removal of material of said micro-peaks of the surface of the workpiece.