Abstract: “3S ladies” have become an increasingly prominent phenomenon in society and provoke serious thoughts by both the public and scholars.Based on Parsons′ theory of structure of social action，this paper，with the “3S lady” phenomenon as an example，studies the function of female model in analyzing female action.The authors try to interpret different marriage systems，and similarities and differences between collective and individual female from the perspective of model variables.The study is hoped to reveal the evolution logic and behavior changes in such phenomenon and to achieve an integrated viewpoint of role selection of 3S ladies.

Key words: 3S lady, female model, model variables, role selection