In order to achieve the precision evaluation and error compensation to the integrated test platform of ball screw, error analysis to the integrated test platform of ball screw was made. The stiffness and thermal deformation of the system were analyzed, which affected the positioning error of the test platform. The mechanical model and thermal analysis model of the ball screw were improved.The positioning error calculated by the improved calculation model was compared with the experimental results, which verified the validity of the new model. This provides a new effective method for the error analysis of the integrated test platform of ball screw, and has a well application value.