Abstract: Antenna spatial oriented direction is taken as variation to study the spatial polarization characteristic of phased array.The polarization property of electronic scanned linear dipole array is derived.A planar phased array antenna with 265 elements is designed by using XFDTD.The co-polarized and cross-polarized component of far field is computed.The changing rule of typical phased array polarization characteristic in different beam position is obtained by spatial polarization character istic.Result shows that the spatial polarization characteristic of phased array is more complicated than mechanical scanned antenna,and its polarization states change with scan angle,element polarization property and some imperfect factor like element coupling.The changing rule is nearly linear variation.The conclusion is consistent with theory analysis.It provides theoretical base and support for the application of the spatial polarization characteristics of the antenna.