The topic of the paper is devoted to analysis of environmental ethics significance for tourism, including experience so far in this domain. Having in mind heterogeneous impacts of tourism activity on natural and socio-cultural environment, development of environmental ethics is a crucial tool for harmonization the relation between this activity and environment. Special attention is focused on discussion on the following issues: ecological awareness and ecological behaviour in tourism, and significance of environmental ethics for tourism sustainability. Concept of sustainable tourism primarily requires essential ethical changes among all participants of the tourist process. If significance of basic ethical principles is reached by consensus and if those principles became, as a precondition for action, a key component in the decision making process, one can expect positive results and the development of tourism on a sustainable basis. This concept has been marked as a paradigm of tourism development in the 21st century, but which, obviously, can not be implemented without defining a clear ethical framework, norms and principles that would be kept up by all stakeholders in the tourism. However, ethics in general, and environmental ethics in particular, becomes an essential tool for the implementation of sustainable tourism concept in a globalized tourism market. Having in mind that tourism is a complex global phenomenon, it is clear that the implementation of ethical principles and standards must spread upon the whole tourist sector, regardless of market niche, and some forms of tourist market. [PUBLICATION ABSTRACT]