The right to a healthy environment has been recognized as one of the subjects of the third generation of human rights by international documents. Thus, the philosophical foundations of the right to a healthy environment arise from conceptions of value, utility, and need, the effects of which can be found in environmental declarations, for example, the Stockholm Declaration. In the framework of need theory and the concept of sustainable development, humans’ need for a healthy environment is recognized as the basis of the right to a healthy environment. In accordance with utility theory, the environment that has the maximum of health and interest and the minimum of pain (for example, pollution) for human beings or animals is recognized as the object of the right to a healthy environment. However, value theory explains the conception of value as the basis of the right to a healthy environment in the framework of existentialism and naturalism theories and recognizes human beings, animals, other creatures, and the planet Earth as right-holders of the right to a healthy environment.