Abstract:The focus of argumentation of western political philosophy experienced a transformation from politics’ moral goal to politics’ moral basis.In ancient time,political philosophy usually took politics’ moral basis as a natural elements with few attention on it,so they focused on argumentation politics’ moral goal;since modern times,political philosophy argued that political relations are man,so they heavily focused on arguing politics’ moral basis,however,there were some doubts in their mind about politics’ moral goal.Actually,only when politics’ moral basis is rigidly argued,can we define politics’ moral goal.