|Millennium:||1st millennium BC|
|108 BC by topic|
Year 108 BC was a year of the pre-Julian Roman calendar. At the time it was known as the Year of the Consulship of Galba and Hortensius/Scaurus (or, less frequently, year 646 Ab urbe condita). The denomination 108 BC for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.
- Roman forces under Quintus Caecilius Metellus Numidicus defeat the forces of Jugurtha of Numidia at the Battle of the Muthul, with Gaius Marius as a subordinate.
- The Korean kingdom of Wiman Joseon falls, and Chinese Emperor Wu of Han establishes the Lelang Commandery in northern Korea.
- December – The Han Dynasty Chinese under commander Zhao Ponu are victorious in the Battle of Loulan in the Tarim Basin, resulting in the submission of Dayuan and the Wusun in Central Asia.