Black cube may refer to:
- Black Cube, a private intelligence agency
- Black Cube Nomadic Art Museum, a nonprofit contemporary art organization producing site-specific art in the public realm.
- Blackballing, a vote of rejection in a secret ballot
- The Kaaba, a black cubical building at the center of the Grand Mosque of Mecca; it is the most sacred site in Islam
- Tefillin, a small black leather cube used by Jews during prayer