Constructivism has had a great influence on science education over the last two decades. The purpose of this article is twofold: First, to describe the characteristics of constructivism and, second, to suggest an ideal forms of science education in Korea as implied in constructivism. A review of the literatures in the first area shows that constructivism is philosophical/psychological view which believe in the social nature of the construction of scientific knowledge and its learning. And the analyses of a few schools of constructivism suggest decision-making as a goal of science education, learning as the active construction of meaning through interaction between learner and learning environments, and discussion and cooperation as appropriate teaching strategies. At the same time, the results necessitate teaching ethical aspects of science in the secondary schools, and also imply that performance assessment must be emphasized in evaluation of science education.