Abstract: This article summarizes the no identical expression situation on aqua ammonia and ammonium hydroxide in domestic and foreign relative chemical teaching materials,professional dictionaries,national standards,relative references of chemistry and chemical engineering.It emphasizes that the description on the nature of chemical reagent aqua ammonia is too simple in the newest national standards,and its Chinese name is embarrassed with chemical formula.Because of more English terms of aqua ammonia and ammonium hydroxide,it is very difficult to unify their Chinese terms.The suggestion is proposed for specification on the terms of aqua ammonia and ammonium hydroxide.

Key words: aqua ammonia, ammonium hydroxide, representation, specification