The invention provides an external member with an English signboard for signing experiment reagent grade and a method thereof. The external member comprises a reagent bottle, a reagent bottle plug, a binding band and an English signboard; the binding band is used for binding the reagent bottle with the reagent bottle plug; a pre-printing identifying zone and a blank identifying zone are arranged on the English signboard; background color of the pre-printing identifying zone in the English signboard and the English abbreviation printed thereon can be set, and the color and shape of the English signboard can be further set so as to identify the purity grade of the experimental reagent in the reagent bottle; when corresponding experiment is carried out, the external member which has been classified and identified the concentration grade of the experimental reagent is selected to prepare or store solution or use the reagent in the reagent bottle to carry out the experiment. The external member realizes the binding between the reagent bottle and the reagent bottle plug, is convenient to manage the reagent bottle; meanwhile, the external member can more perfectly and exactly realize the classified use of the experiment reagent grade, save cost, and improve the working efficiency.