The educational system for postgraduate students is flexible in some of universities in China. This study aimed to examine why the postgraduate students choose to graduate earlier and what are the leading factors to make them graduate earlier successfully. This case study employed methods of interviews，non-participant observations，and materials collections to study four female students who got the early graduation from B. university that has implemented the Flexible Educational System for postgraduate students. The finding leads to the following observation：（1）The early graduation was driven by the students’ level of expectation for academic organization. The students entered with the assumption that the postgraduate education should correspond with and improve their academic ability and social economic status. However，during the postgraduate education process，it is the attraction of social economic status，not need for academic knowledge and ability motivated them to choose early graduation；（2）Early graduation illustrated the power relationships between higher education institution，organization and individuals，in which higher education was disadvantaged. The dynamics of early graduation came from the job market not the education system. With the influence of the job market，the university adjusted the training goal and approach，the second-tier colleges changed the academic requirements，and the postgraduate supervisors were forced to compromise or lower their academic standards.