| Conflict: | Siege of Thessalonica (254) |
| Partof: | the Crisis of the Third Century Gothic War (248-253) and Roman–Germanic Wars |
| Date: | 254 |
| Place: | Thessalonica, Macedonia, Roman Empire (present-day Macedonia, Thessaloniki, Greece) |
| Map Type: | Greece Thessaloniki#Greece |
| Map Relief: | y |
| Result: | Roman victory |
| Combatant1: | Roman Empire |
| Combatant2: | Goths |
| Commander1: | Unknown |
| Commander2: | Unknown |
| Strength1: | Garrison Militia |
| Strength2: | Unknown |
The siege of Thessalonica in 254 was a successful defense of the city of Thessalonica by local Roman militia during an invasion of the Balkans by the Goths.
In 254 the Goths invaded and plundered Thrace and Macedonia. In 1979, Herwig Wolfram regarded 254 as the date, while Mallan and Davenport in 2015 suggested 262. Goltz and Hartmann estimated 254 as the date. David Potter in 2016 rejected Mallan and Davenport's estimate and dated it to either 253 or 259.
The Goths attempted to storm Thessalonica in close order formations and assault columns. The Thessalonicans rallied to defend the city walls and defeated the attacks.
The Goths abandoned the siege and moved on to invade Greece south of Thermopylae, seeking to loot the gold and silver wealth of Greek temples. The siege was recorded by the contemporary historian Dexippus. A fragment of his work, discovered in Vienna in 2010, specifies the involvement of the citizens in the defense.