In order to research the influence of the base motion on the dynamic performance of the parallel mechanism, the six DOFs parallel adjustment mechanism of the Shanghai 65 meters radio telescope was selected as the study object, through theoretical calculation and simulation analysis to get the result of the research. Firstly, the configuration of the parallel adjustment mechanism was introduced, and six position parameters of the moving platform were selected as the generalized coordinates of the system to describe the position and the posture of the moving platform. Secondly, the force influence of the movement of the base on the moving platform and each driving branch was deduced, and the change of the direction of gravity vector caused by the movement of the base was analyzed, the Kane method was used to establish the dynamic equations of the parallel adjustment mechanism in the case of base fixing and moving. At last, the structure of the parallel adjustment mechanism and its physical parameters were set, the numerical and simulation analysis were carried out by Matlab and ADAMS software, respectively, the driving force variation curve and the contrast curve of each driving branch were obtained in two cases. The results of the two software simulations were the same, which verified the correctness of the dynamical model, through the contrast of the curves, it was also found that the influence of base motion on system dynamics was obvious, and it should be considered during the he structural strength check and control system parameters setting, so that the reliability of the control system and the reliability of the structural strength can be improved.