This paper investigates the dual role of the civil society non-governmental organizations in Taiwan's whole process of democratization, that is, their role first in facilitating and promoting liberalization and later in strengthening and materializing democratic consolidation. In the former stage, social movements or advocacy non-governmental organizations have performed an outstanding job, and during the latter phase, both advocacy and service providing non-governmental organizations have exerted their respective influences on democratic governance. Based on an empirical survey on non-governmental organizations, this paper also delineates the autonomy, advocacy, and influence that most of Taiwan's non-governmental organizations have already enjoyed under the context of democratic governance. Finally, the changing relations between social movements and the DPP government after it took power in 2000 are then analyzed by using the cases of labor movements, welfare movements, and environmental movements to demonstrate the challenge and complexity of new democratic governance faced by Taiwan in its post-democratization era.