A buffer zone is a neutral zonal area that lies between two or more bodies of land, usually pertaining to countries. Depending on the type of buffer zone, it may serve to separate regions or conjoin them. Common types of buffer zones are demilitarized zones, border zones and certain restrictive easement zones and green belts. Such zones may be comprised by a sovereign state, forming a buffer state.

Buffer zones have various purposes, politically or otherwise. They can be set up for a multitude of reasons, such as to prevent violence, protect the environment, shield residential and commercial zones from industrial accidents or natural disasters, or even isolate prisons. Buffer zones often result in large uninhabited regions that are themselves noteworthy in many increasingly developed or crowded parts of the world.