Wall thickness measurement is an indispensable and very important item in the process of pressure vessel inspection.This paper mainly aims at the problems related to wall thickness measurement in pressure vessel inspection,studies the specific method selection of wall thickness measurement,determines different thickness measurement schemes for different corrosion conditions such as point corrosion,uniform corrosion,local corrosion,and if necessary,carries out strength checking calculation according to the remaining wall thickness,and puts forward the matters that should be paid attention to in the process of wall thickness measurement.Focus on the retest of the original wall thickness,the influencing factors of the measurement values,and the key points of operation of wall thickness measurement,so as to provide the reference for obtaining accurate wall thickness measurement data.