It is well discussed and elaborated that the education in China has contributed greatly to China’s economy growth miracle. However, it needs further studies that why China’s education can expand so fast without school funding from governments. By constructing a simultaneous equation model for panel data with single error component, this paper empirically examines the relationships among the ratio of female employment, relative wages in education sector and the expansion of post-secondary education in China. 3SLS regression results show that the increase in the share of women employment in education sector significantly reduces the relative wages in education sector, and a relatively low wage level in education sector also supports the rapid expansion of post-secondary education. The reason lies in that, although the relative wages in education sector are relatively low, higher stability and security of employment in education sector have attracted more and more women workers who are willing to choose a relatively more stable job and give up a part of the money income. Due to inadequate government funding for education for a long time, the education sector can hire a higher proportion of women to keep the relative wages at a low level, so as to control the costs of education and enable rapid expansion of post-secondary education and human capital accumulation. The long-term impacts of post-secondary education expansion, which is supported by the high proportion of female employment and low wages, on the economic and social development need further studies. However, the low wage level in education sector may not be conducive to enhancing staff enthusiasm and attracting more talented people into the education sector, therefore the average wage level in the education sector should be increased in the future.