Abstract: The measurement of hollow turbine blade wall thickness based on industrial CT images is affected not only by the quality of CT image,but also by the applied methods which shall also result in different outcomes.At present the commonly used wall thickness measurement method is the half-height method based on gray value change curves and the semi automatic measuring method based on image segmentation.Artificial test blocks of two specifications were designed and tested by industrial CT,and the half height method and semi automatic measurement of wall thickness were conducted to measure the wall thickness and the related results were analyzed.The results show that the half height method and semi automatic measurement method can get more accurate wall thickness data,but the efficiency of semi automatic measurement method is higher than that of half height method.