In industry, the pH meter is used more frequent as a pH measuring and analyzing instrument rather than the pH test paper and standard colour chart. The digital pH meter display screen can accurately show the pH value on real time, the error is greatly increased by one order of magnitude than that of pH test paper. Moreover, it can also realize the automatic control of pH value and pH value alarm. But due to the service life of pH electrodes, it is easy to break down, as a result, users have to pay much money in replace new pH electrodes. Next we will introduce the selection experience of pH electrode in several typical industries, so as to provide reference for users.