The invention has for its object the provision of a cleaner capable of removing particles and metal impurities present on the surface of a wafer without corrosion of wirings, gates or the like yet at normal temperature in a short period of time and with a one-pack type solution. To accomplish the above object, the invention provides a cleaner that is an aqueous solution containing phosphoric acid, hydrofluoric acid, and ammonia and/or amine, and having a pH ranging from 2 to 12, wherein the aqueous solution comprises 0.5 to 25 mass % of phosphoric acid, 0.1 to 10 mass % of ammonia and/or amine, and 5.times.10.sup.-3 to 5.0 mass % of hydrofluoric acid.