Abstract: Through the analysis of the data of the “social network and job search survey” in 2014 and 2016， it is found that the change of educational achievement and the way of position acquisition of the workers after they get their first jobs have different influence mechanisms on the career status. Different education diplomas have different incentives for workers after their first employment， and the adult higher education is more likely to attract people to “further study”. Job seekers who use “guanxi” to get their first jobs are more likely to change their educational achievements in the future. Those who use “guanxi” to get their current jobs are more likely to achieve upward social mobility， but the impact of changes in educational achievements on the rise of professional status is not significant. The change of educational achievements after the initial employment only compensates for the deficiency of educational signal and does not solve the crisis of trust in employers' ability to work like the social ties.

Key words: educational achievement change, further study, social ties, career status, educational signals