The geosynchronous synthetic aperture radar (GEO SAR) can achieve staring observation for a long period, either to monitor the target area continuously or to improve the resolution due to its ultrahigh orbit. Taking into account of the state of art of antenna, a novel beam steering strategy of united control of satellite attitude and antenna beam is proposed and derived to implement staring at target area based on the characteristics of GEO SAR staring imaging. Besides, the visibility for a ground target is analyzed based on the basic methodology of staring observation. The feasibility of the proposed method is analyzed and verified by simulating a ground target imaging in different orbit positions.