The purpose of this research is to explore the relative plausibility of the arguments of political power and government regulation theories by examining the politics of the Korean environmental policy from the 1960s to the early 1990s with a longitudinal perspective. Major environmental laws, the designation of the Phaldang and Daechung Dams (main water resources for Seoul City, Kyungki Province, and Choongchung Provinces) as special treatment areas for protection of water resources, and the Korean government's responses to the environmental incident of the phenol flow into water supply pipes were examined. Theoretical resources for the study of the politics of the Korean environmental policy can be divided into two large domains: political power and government regulation theories. Political power theories can be divided into two main groups: society-centered and state-centered approaches. The former includes the pluralist and class approaches. The latter includes the state interest and bureaucratic politics approaches. Government regulation theories can be also divided into the "public interest" and "capture" approaches. James Q. Wilson's theory of the politics of regulation based on regulation types are also utilized. With a different perspective from political power and regulation theories, Wilson emphasized that we need to approach the politics of regulation more specifically based on regulation types because different types of government regulation involve different types of political actors. Several hypotheses drawn from these theoretical arguments are tested. We can find two important things from this research. The first thing is that there is no single dominant approach that can explain the politics of Korean environmental policy over the entire range of cases. Korean environmental policy of the 1960s and the 1970s can be best explained by the state interests approach and the capture approach. Like the 1960s and 1970s, the 1980s show that Korean environmental policy can be best explained by both the state interests approach and the capture approach. Unlike environmental policy of the 1960s/1970s and the 1980s, environmental policy of the early 1990s can be best explained first by the public interest approach, and then by the capture approach. The second thing is that although there is no single dominant approach to explain Korean environmental politics, this research shows that as the Korean political system becomes more democratic, the relative plausibility of the society-centered approaches is greater than the state-centered approaches in the area of environmental policy. Also, as Wilson argues, we should keep in mind that in the area of social regulation (environmental policy), without serious environmental incidents and the roles of the mass media, the possibility of the capture of government by business groups is very great because regulated groups will be more eager and apt to organize in order to avoid concentrated costs than public interest groups with diffuse interests