The International Standard ISO 4802.1 – 1988 “Water Resistance of the Inner Surfaces of Glassware, Glass Containers, Part 1: Determination and Classification by Titration” defines borosilicate glass (including neutral glass) as glass containing boron trioxide (B-2O-3) in the range of 5 to 13 % (m/ m), but ISO 12775 “Classification of the Composition of Glasses for Normal Large-Scale Production” published in 1997 defines borosilicate glass (including neutral glass) as containing more than 8 % (m/ m) of boron trioxide (B-2O-3). However, ISO 12775 “Classification of Composition of Glasses for Normal Mass Production and Test Methods Thereof” published in 1997 defines borosilicate glass (including neutral glass) as containing more than 8 % (m/ m) of diboron trioxide (B-2O-3). According to the principle of glass classification in 1997 international standard, the glass material of B-2O-3 about 6% (m/m) widely used in China’s pharmaceutical glass bottle industry for many years should not be called borosilicate glass or neutral glass. Tests have proved that the water resistance of this type of glass by granular method and the water resistance of the inner surface are not up to Grade 1 and HC1, or are on the edge between Grade 1 and Grade 2. Practice has also proved that some of these glasses in use will be unqualified or dislodged phenomenon of neutrality, but this kind of glass has been produced and used in China for many years, the new standard retains this kind of glass and provides that the content of B-2O-3 should meet the requirements of 5 – 8 % (m / m), a clear definition of this kind of glass can not be called borosilicate glass (or neutral glass), and will be named as low borosilicate glass.