The purpose of the present invention is to provide an aqueous preparation for external use, said aqueous preparation comprising an acidic drug such as an arylacetic acid nonsteroidal anti-inflammatory analgesic, having an excellent percutaneous absorbability and giving a good feeling in use. The aqueous preparation for external use comprises the acidic drug or a salt thereof, isostearic acid and an alkanol amine. It is preferred that the aqueous preparation according to the present invention for external use further comprises a C 2-6 aliphatic hydroxy acid and has a pH value of 4.5-7.8. The C 2-6 aliphatic hydroxy acid is one member or a combination of the same selected from the group consisting of lactic acid, glycolic acid, malic acid, tartaric acid and citric acid.