This paper analyzes the sensitivity of large-scale generator stator ground protection, and proposes the concept of 2-section type of generator stator ground protection based on the zero sequence voltage of fundamental wave, i.e., the low setting for sending signal and the high setting to trip and shutdown. The setting of large-scale generator stator ground protection and the relation between various settings are described. Through cooperating each other between the generator stator ground protection, it can operate sensitively when single phase ground fault in whole range of generator stator winding occurs.