The transformation of Taiwan’s fishery has been guided by the idea of ’sustainable development’-a concept originated from Aldo Leopold’s theory of ecological equilibrium. In this paper, I discuss the concepts of sustainable development and ecological equilibrium and examine both the theoretical and practical problems of the two concepts and their application in Taiwan’s fishery industry. Furthermore, the study argues for the idea of life rights of animals developed in Peter Singer’s Animal Liberation. I suggest that the idea of life rights of animals should be a key element in any program of sustainable development and ecological equilibrium.