The GPS (Global Positioning System) receiving antenna installation angle on a quasi-inertial orientation of the exploration-satellite is studied. Firstly, according to the mission requirements, the satellite attitude requirements are analyzed. Secondly, theoretical analysis and simulation were conducted according to the attitude requirements of posture on the installation of the GPS receiver antenna installation angle, preferably by the GDOP (Geometric Dilution of Precision) values. Finally, conclusion is drawn based on the simulation results that the GPS receiving antenna axial is near to the ± y
axis of body reference frame, viz. the orbital plane normal or negative normal direction.