Laser tracker measurement technology is widely used in assembling, manufacturing and other fields. For the study of the laser tracker measurement accuracy, a set of coordinate measurement accuracy testing system is developed, which can realize synchronous trigger of motor motion control, grating scale acquisition and laser tracker measurement through multi-axis motion controller based on the data collected by grating scale. The repeated positioning accuracy of the system and the synchronous trigger coordinate measurement accuracy of the laser tracker are tested respectively. The results show that the system repeated positioning error is between [–4.0 μm, 4.0 μm]. When the distance between three laser trackers and the target mirror in the tangential direction is [2.7 m, 3.4 m], the coordinate measurement error varies with the velocity between [–23 μm, 988 μm]. When the distance between laser tracker and the target mirror in the radial direction is [1.5 m, 3.8 m], the coordinate measurement error varies with velocity between [5 μm, 915 μm].