Disclosed are an etchant which is used for the manufacture of a semiconductor device using a semiconductor substrate having an electrode and which is capable of selectively etching copper without etching nickel, and a method for manufacturing a semiconductor device using the same. Specifically disclosed are an etchant to be used for the manufacture of a semiconductor device using a semiconductor substrate having an electrode, including hydrogen peroxide, an organic acid, and an organic phosphonic acid, wherein the organic acid is at least one member selected from citric acid and malic acid; a content of hydrogen peroxide is from 0.75 to 12% by mass; a content of the organic acid is from 0.75 to 25% by mass; and a content of the organic phosphonic acid is from 0.0005 to 1% by mass, and a method for manufacturing a semiconductor device using the etchant.