The invention discloses a method for efficiently separating copper and arsenic in copper smelting smoke dust, and belongs to the technical field of wet metallurgy. The method comprises the steps of pulpifying the copper smelting smoke dust by adopting appropriate amount of water, a dilute sulphuric acid solution and a two-stage leaching solution, and leaching at the atmospheric pressure, wherein metallic oxide such as arsenic, copper, iron, zinc and cadmium in the smoke dust and salts are leached to enter a solution, and sulphides such as copper and arsenic hard to leach are remained in slags;and pressure leaching the leaching residues, so that the leaching rate of the arsenic and the copper is further improved, and the copper and the arsenic in the smoke dust are efficiently removed andrecycled. The invention provides the method for conveniently, quickly and efficiently removing the arsenic and the copper in the copper smelting smoke dust, so that the grade of slag containing lead and bismuth is improved; and the leaching solution is used for producing white arsenic or metal arsenic and recycling valuable metals such as the copper.