Demarcation is the act of creating a boundary around a place or thing.
Demarcation may also refer to:
- Demarcation line, a temporary border between the countries
- Demarcation problem, the question of what theories or beliefs lie within the boundaries of science
- Demarcation dispute, may arise when two different trade unions both claim the right to represent the same class or group of workers
- Demarcation point, in telephony, the point at which the telephone company network ends and connects with the wiring at the customer premises