In order to obtain the correct and reasonable result from bogie parameters test, the principle of bogie parameters test rig and the reason of experimental error were analyzed. An effective and simple data-processed software for the test rig was developed by using VB and Matlab based on ActiveX technology. The error was rejected by the data-processed software. The data-processed method for positioning stiffness and bogie rotational resistance was introduced in detail. The evaluation criteria of bogie rotational resistance was summarized. The feasibility of the software was verified by processing a set of measurement data got from CRH₅ bogie parameters test. The result indicates that each bogie rotational resistance is less than 0. 08. Bogie rotational resistance in deflated air spring state is bigger than that in the inflated state under the same actuator loading frequency. Under the same air spring condition, bogie rotational resistance increases as actuator loading frequency increases. Therefore, it is shown that vehicle's speed and the conditions of air spring have certain impact on vehicle's curving performance. 2 tabs, 6 figs, 10 refs.