During the period of Nansong Dynasty,the position of Ci is increased,the people of the same time begin to edit the selections of Ci.There are five omnibus selections of Ci compiled by the people of Song Dynasty now.According to the specific analyses of five selection's aesthetic style,the same point can be concluded,that is to say,the soft style is the most important style.Then the paper researches the objective reason ahd the subjective reason of this phenomenon and gives detailed explanation.