A cleaning liquid is provided, which comprises an aqueous solution containing nitric acid, sulfuric acid, a fluorine compound, and a basic compound. The concentration of water in the cleaning liquid is 80% by weight or more, and the pH value of the cleaning liquid is from 1 to less than 3. The cleaning liquid is effective for removing etching residues formed in a dry etching process from semiconductor devices and display devices without oxidizing and corroding their metal wirings, particularly, copper wirings and the materials of insulating films.