Abstract: A certain magmatic liquation nickel sulfide ore is from Shaanxi Province with nickel grade of 0.53%.Serpentine and talc，as the main gangue minerals，is easy to be slimed and have good floatability，and the valuable minerals are not easy to be liberated from the gangues.By adopting the process of three roughing-one cleaning-two scavenging and middling back to the flowsheet in turn，nickel concentrate could be obtained with only 5.12% Ni and 68.40% recovery.In order to increase the resources utilization and enterprise's benefits，electrochemical control flotation experiments were carried out.The results indicated that：using DHN as electrochemical control agent，nickel concentrate with nickel grade of 5.20% and recovery of 73.78% was obtained under the same grinding fineness and process.Compared with the on-site concentrate，nickel grade was increased by 0.08 percentage points，while the recovery rate was increased by 5.38 percentage points.The method has good performance in improving the concentrate amd is easy to be put into practice as well.

Key words: Refractory nickel ore, Electrochemical regulating flotation, Electrochemical control agent DHN