Abstract: The oil chamber is an important structure for cooling inside the piston, and its position has an important impact on the working temperature of all parts of the piston. For the measurement of the wave-shaped oil chamber position, some difficulties may exist, such as that the linear array industrial CT is not applicable and the ultrasonic detection can not be performed. The industrial CT method for the position measurement of the wave-shaped oil chamber is studied. It is based on the DR and linear array industrial CT to set the setting of scanning position and determine the minimum number of sections. The method is verified, which shows that the measurement error is within 5%. The method has lower detection cost and higher detection efficiency.