Lligwy Burial Chamber is a Neolithic burial chamber in Lligwy, near the east coast of Anglesey, Wales, United Kingdom. It consists of a circle of upright stones, made into a low chamber by a very large roof slab estimated at 25 tonnes. Excavation in 1909 found the remains of some 15 to 30 people, and pottery suggesting a late Neolithic date. Close to the village of Moelfre, the site is within a few metres of the road, where there is room to leave a single car for short periods.

Lligwy Burial Chamber is a very robust, neolithic chamber. The eight uprights which support the massive capstone are larger than they at first appear, because half of their 2 m (6.6 ft) height is buried in the ground. The capstone is about 5.5 m (18.0 ft) long and 4.5 m (14.8 ft) wide, with a thickness of around 1 m (3.3 ft). It is estimated to weigh about 25 tonnes (28 tons) and is in contact with only three of the uprights. A gap between the uprights on the eastern side probably indicates where an entrance passage stood, with a way out of the mound; It is unclear whether this chambered tomb was covered by a cairn, but if it was, no trace remains today. Deep grooves in the limestone capstone imply that erosion by rainfall has taken place, further evidence that the structure may not have been covered by a cairn.