Poulnabrone Dolmen (Poll na mBrón in Irish meaning "hole of sorrows") is a portal tomb in the Burren, County Clare, Ireland, dating back to the Neolithic period, probably between 4200 BC to 2900 BC. It is situated 8km (5 miles) south of Ballyvaughan and 9.6km (6 miles) north-west of Kilnaboy.

The dolmen consists of a twelve foot, thin, slab-like, tabular capstone supported by two slender portal stones, which lift the capstone 1.8m (6ft) from the ground, creating a chamber in a 9m (30ft) low cairn. The cairn helped stabilize the tomb, and would have been much higher originally. The entrance faces north and is crossed by a low sill stone

A crack was discovered in the eastern portal stone in 1985. Following the resulting collapse, the dolmen was dismantled, and the cracked stone was replaced. Excavations during this time found that at least 22 adults and children were buried under the monument. Personal items buried with the dead included a polished stone axe, a bone pendant, quartz crystals, weapons and pottery. In the Bronze Age, around 1700BC, a newborn baby was buried in the portico, just outside the entrance. With its dominating presence on the limestone landscape of the Burren, the tomb must have remained a centre for ceremony and ritual until well into the Celtic period.