| Conflict: | War between the Argentine Confederation and the State of Buenos Aires |
| Date: | 1852-1862 |
| Place: | Argentina |
| Result: | Buenos Aires victory
|
| Combatant2: | Buenos Aires |
| Commander1: | Justo J. de Urquiza |
| Commander2: | Bartolomé Mitre |
| Strength1: | 1852: 2,500 regulars 83,000 national guardsmen 1858: 121,500 men |
| Strength2: | 1852: 3,500 regulars 70,000 national guardsmen 1863: 41,514 men |
| Partof: | the Argentine Civil Wars |
The war between the Argentine Confederation and the state of Buenos Aires was a conflict of the Argentine Civil War. It began with the secession of Buenos Aires from Argentina, and lasted from 1852 to 1862. With the military victory of Buenos Aires at the battle of Pavón, the country was unified again.