Chinese society shows a multi-dimension structure, namely structural stratum and pyramid-shaped class. Scholars tend to ignore the difference between stratum and class. After Reform and Opening-up, the development of China's stratum has showed multiple cross-border movements due to the frequent stratum mobility and the repaid polarization of the society. Combined with the three leading factors resulting in stratum solidification, this paper derives several models of modern society mobility and compares them by choosing the principle of social justice.