109 BC

Year 109 BC was a year of the pre-Julian Roman calendar.

At the time it was known as the Year of the Consulship of Numidicus and Silanus (or, less frequently, year 645 Ab urbe condita) and the Second Year of Yuanfeng.

The denomination 109 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.