Abstract: On the basis of the relative positioning method and the revolving method,by using the precise leveling,a new method is put forward for examining the antenna phase center three-dimensional bias of GPS receiver with the geometric relation of the antenna phase centers and the mini baseline.The examples and results show that the antenna phase center bias of the same type of GPS receivers is close to the homology,and the difference in vertical heft is up to millimeters.Those of the different type receiver antennas have much more differences.