Given article examines existing definitions of the notion of environmental policy, identifying main approaches and differences between them. It shows many authors presents it as environmental protection “course of actions”, “scopes and objectives”, “state and/or non-state activities in the domain”, “totality of principles, mechanisms and tools” etc. It also gives a new definition which specifies environmental policy is a system of principles, goals and objectives as well as of mechanisms and tools for their achievement which are applied to ensure an efficient environmental protection as part of sustainable development. The article contains also an overview of the main principles of the environmental policy applied in environmental management and sustainable development.