The article discusses the basic principles of environmental ethics and the characteristics of the principle of biodiversity. The principle of biodiversity has the characteristic features of elevating moral values regarding the moral and 89 caring attitude of a person to the world around. The article describes the main directions of environmental ethics and principles of biodiversity. Biological diversity is the diversity of all life on Earth, from gene-based ecosystems, including all types of animals, plants and microorganisms that inhabit all the habitats of the planet. It "permeates" each of the three main levels of the organization of living matter, hence the three branches of biodiversity: genetic, species and environmental. Biological diversity at the species level covers the entire range of species on Earth from bacteria and protozoa to the kingdom of multicellular plants, animals and fungi. On a smaller scale, biodiversity includes genetic diversity of species formed by both geographically distant populations and individuals within the same population. Biological diversity also includes the diversity of biological communities, species, ecosystems formed by communities and the interaction between these levels. All levels of biological diversity are necessary for the continuous survival of species and natural communities. According to the famous biologist Edward Wilson, biodiversity is the very essence of life.