Defence of the Realm (disambiguation)

Defence of the Realm might refer to:

• Defence of the Realm, a 1985 political thriller film
• The Defence of the Realm, a 2009 history of MI5 by Christopher Andrew
• Defence of the Realm Act 1803, an act of the United Kingdom parliament
• Defence of the Realm Act 1914, an act of the United Kingdom parliament
• Defence of the Realm Act 1915, an act of the United Kingdom parliament