It is necessary to control and measure the initial assembly precision of the table when assembling the components of the CNC turntable. In order to improve the detection efficiency and test reliability of the turntable, a precision testing device for the CNC turntable applicable to the table with multi-size specification is researched and designed, which is convenient for the multi-dimensional measurement of the rotary positioning and flatness of working table in the range of size. The working principle and structural characteristics of the detection device are introduced in detail. The key structural design is simple and compact, flexible and convenient operation, the test efficiency compared with the existing technology to improve 5–10 times, optimization and improvement of detection technology and efficiency, for improving the accuracy of the rotary table and the realization of the multi-axis linkage machining and manufacturing has a certain value of engineering applications.