| Conflict: | Siege of Thorn |
| Partof: | the Great Northern War |
| Date: | May to October 14, 1703 |
| Place: | Toruń, Poland |
| Map Type: | Poland Kuyavian-Pomeranian Voivodeship#Poland |
| Map Relief: | y |
| Territory: | Thorn surrenders to the Swedes |
| Result: | Swedish victory |
| Combatant1: | Swedish Empire |
| Commander1: | Charles XII |
| Commander2: | von Kanitz |
| Strength1: | 26,000 men |
| Strength2: | 6,000 men |
| Casualties1: | 50 dead |
| Casualties2: | 1,000 dead 4,860 captured |
The siege of Thorn was set during the Great Northern War, between Sweden and Saxony from May to October 14, 1703. The Swedish army was commanded by Charles XII of Sweden and the Saxon by General von Kanitz. The siege ended with a victory for Sweden, and the whole garrison surrendered to the Swedes.