Abstract: In the process of automatic wall thickness measurement, it is difficult to ascertain the position and posture of measuring points in thin-walled rotary parts. In order to solve the problem and improve measurement efficiency, an automatic measurement method on wall thickness of rotary workpiece is proposed based on the multi-degree-of-freedom manipulator. The characteristic curve is reconstructed using the data measured by Laser Displacement Sensor. The position of measuring points is obtained by the adaptive placement strategy of characteristic curve. Automatic thickness measurement by robot is realized.