This paper investigates any precursor to the central government‘s organizational reforms in Korea. The research has started from questioning what factors create, abolish, expand, or downsize the ministries of the central government. This study examines the role of the government in reshaping ministrial structures. First, while the government takes initiatives in organizational reforms primarily during the pre-democratization era, the number of environment-dependent reforms have been increasing afterwards. Second, the causes of reforms have increasingly become complex. The bureaucratic expansion, however, has been a general trend throughout time. This has brought some positive consequences; but it cannot always avoid criticism. The discussion of these factors serves as a core to understanding the fundamental features of the Korean government system. It will also point out possible challenges and drawbacks the government may confront in the future.