In order to reduce the influence of base station layout on the measurement result in the machine tool precision detection by multi-station and time-sharing measurement with laser tracker, the research on optimization of base station layout is conducted. The influence of location layout of base station on its calibration accuracy by multi-station and time-sharing measurement is analyzed. The positional dilution of precision (PDOP) in global positioning system (GPS) measurement is applied as an indicator to evaluate whether the layout distribution of base station is reasonable or not, and the optimization function of base station layout is established. On this basis, the optimal layout position of base station is determined according to the established base station distribution optimization function for three different motion regions (1D line, 2D plane, 3D space) of machine tool during measurement. The distribution law of PDOP at different space positions is also analyzed, which can provide a reference for the reasonable distribution of base station layout in field measurement.