In this paper，by uiewpoints of system engineering we study the solutions of n-person noncooperative games，give two new refinement types of Nash equilibrium point: 1st Nash eqai1ibrium point (1st Nash e.p.)and 2nd Nash equilibrium point (2nd Nash e.p.)，and prove its existence. There is risk in the 1st Nash e.p，conservation in the 2nd Nash e.p，both e.p. satisfying the global optimization.