Among all contemporary world's discourses that influence environmental design profession, sustainability appears to be a dominant and compelling narrative. The developing trajectory of sustainability in architecture seems to suggest an antinomy paradigm, a contradiction or inconsistency between two apparently reasonable principles or laws i.e. sustainability and aesthetics. As a result, emerging sustainable design requires an accompanying set of aesthetics which serve as design guidance and evaluation tool. Literature review of philosophy and designing profession realize three kinds of alternative aesthetics i.e. environmental, ecological, and performative aesthetics. The thesis argues that this alternative set of sustainable aesthetics provides a theoretical basis for the practical design of a built environment for eco-tourism. The thesis focuses on analyzing the implication of those aesthetics to sustainability in regards to design of ecolodges. Eco-tourism is one of the emerging pragmatic options of sustainable development and to consume ecotourism is to consume aesthetic experience. By reviewing and analyzing the case studies of ecolodge, this thesis provides the design features and strategies which are argued to integrate beauty and sustainability. The thesis also applies the findings to demonstrate the usefulness of aesthetic approach to sustainable design in one specific design proposal, Floating Bamboo Ecolodge in Halong Bay, Vietnam. / text