Abstract: Single Gimbal Control Moment Gyroscopes (SGCMGs) are torque produ cing devices which are internal to a spacecraft and operate based on principles of momentum exchange.Normally,three or more SGCMGs are used in the spacecraft in order to realize 3 axis control.However,SGCMG systems do suffer from a serious drawback-singularity sometimes,and can not produce desired control torque when many SGCMGs work coordinately.In order to avoid system singularity,distribution of singular points must be studied in gimbal space for SGCMG systems.In this paper,it is proved that the correspondent singular points in gimbal space are finite to any point in angular momentum space for redundant systems which axes are mounted non coplanarly,pyramidally and symmetrily.