The Medieval Siege Society is a British Living history and Combat reenactment association dedicated to costumed reenactment of Siege warfare, Combat reenactment and events surrounding the history known as the Hundred Years War and the Wars of the Roses (circa 1350-1490). Apart from reenactment, it is also involved in research into the history of the period, and education (at the school or college level) about the same.

The Medieval Siege Society frequently performs at heritage sites around the UK and beyond.