Perceptions of risk from nuclear power generation have received considerable attention as a significant determinant of public acceptance of nuclear power-a requirement to draw social and political support for nuclear power generation. However, the distinction between the dimensions of risk perception and the differentiated effects of such dimensions has been less explored. The present study demonstrates that two distinct dimensions of risk perception from nuclear plants-perceived intrinsic risk and extrinsic risk-reveal contrasting patterns of influence on the acceptance of nuclear power. Our results, using a sample from South Korea, show that the relative effect of perceived extrinsic risk from nuclear plants on the acceptance of nuclear power (compared to that of intrinsic risk) is stronger at higher levels of such acceptance than at lower levels. This finding provides implications for public policy to encourage the acceptance of nuclear power. Such policy should selectively choose between the two approaches-reducing the public's perceived level of intrinsic risk and that of extrinsic risk-depending on whether the policy's aims is to soften opposing voices or to promote positive voices for nuclear power.