Abstract: As a new policy instrument of local governments, co-founded university incubators play a significant role in innovation city building and technology commercialization. However, under the homogeneous institutional structure, there is a great difference of organizational performance among co-founded university incubators. In this paper, we use extended case study method to unfold the process of the changing boundaries in TS Incubator which is the first co-founded university incubator in China. We reveal that there are 3 stages of boundary-drawing in the past 20 years, and TS Incubator as a boundary organization has changed its organizational forms 4 times for catering to different actors in the institutional environment. By opening the “black box” of “consensus” and “institutional hybrid”, we also find out the crux of maintain the hybridity of the incubator is not reaching consensus but reserving heterogeneity. Furthermore, institutional pressures and institutional logics are two important variables which influence the results of boundary-drawing.