Reverse positioning is a significant positioning method of rotary table, the positioning displacement error caused by clamping cannot be neglected. Since the direct acting factors are numerous, the mechanism and value of the displacement error are difficult to test. In this paper, we took the general rotary table as the experiment object, designed and manufactured a set of device that could analyze the reverse positioning. According to various measurement conditions, first the stress-strain of all the components was calculated based on the finite element analysis. Then the displacement errors were measured on the experimental device. Finally the comparison between the simulation and the experiment results allowed the improvement of the model, algorithm analysis and the structure of the experimental device. As the theoretical results continued to get close to the measured values, on the basis of the process above can we conclude the influencing factors and the possibility to reduce the error, thus develop a new approach for the reduction of the reverse positioning error.