With the development of non-destructive detection, higher accuracy and efficiency are required for non-destructive detection, that the mode of hand-held probe can't meet the testing requirements, especially for Complex surface parts. While with the help of 6 degree of freedom (DOF) manipulator, the probe can reach any position in the working space, to fulfill the testing task. This paper proposed a method, post-processing technology of point position based on NC code, that the manipulator-held probe can detect the parts along its curved surface. First of all, the 3D (three-dimensional) model of the part should be measured, and imported into the processing module of UG, a kind of 3D software. After setting reasonable process parameters, NC code containing the information of trajectory planning can be got. Through post processing of NC code, the information of trajectory information directly used in manipulator can be obtained. The feasibility of trajectory planning in UG and the correctness of algorithm are verified in the experiment.