| Conflict: | Siege of Deeg |
| Partof: | The Second Anglo-Maratha War |
| Date: | 11-24 December, 1804 |
| Place: | Deeg fort |
| Territory: | British troops capture Deeg Fort |
| Result: | British victory |
| Combatant1: | British East India Company |
| Combatant2: | Bharatpur State Maratha Empire |
| Commander1: | General Lake |
| Commander2: | Unknown Unknown |
| Casualties1: | 227 troops |
| Casualties2: | Unknown |
The siege of Deeg (11–24 December 1804) was a siege of the main fort at Deeg, now in the Bharatpur district of Rajasthan, India, then within the Bharatpur Kingdom. Forces of the British East India Company, led by General Lake, captured the fort from its Marathan defenders.
The siege started on 20 November, the bombardment on 13 December, and a breach made at Shahburz, a salient on the southwest side of the fort, on 23 December. A three-pronged attack took place that night and the Marathas retreated to Bharatpur on the 24th. The British suffered 227 casualties.[1]