The invention discloses a method for preparing a copper-iron nano plated layer from low-grade sulfide ore through direct electro-deposition. The method comprises the following steps: mixing choline chloride and urea in a mole ratio of 1:2, and sufficiently stirring to uniformly mix choline chloride and urea; further adding excessive oxidized roasted sulfide ore powder, and stirring till the valuable metal phase in the roasted powder is completely dissolved in an ionic liquid; by taking an acid activated square titanium sheet as a cathode and a platinum wire as an anode, controlling the temperature of electrolyte to be 80-100 DEG C, the applied voltage to be 1.8V and the electro-deposition time to be 5-7 hours; after electro-deposition is completed, taking out the cathode sheet, washing, and drying in the argon atmosphere at 80-90 DEG C, thereby obtaining a metal plated layer. The method is simple in device, short in procedure and green and environment as the nano metal plated layer is prepared by taking the low-grade oxidized and roasted sulfide ore as a metal source and enriching and extracting metal in the ore through electro-deposition in a choline chloride-urea ionic liquid system.