A ring dike or ring dyke in geology refers to an intrusive igneous body. Their chemistry, petrology and field appearance precisely match those of dikes or sill, but their concentric or radial geometric distribution around a centre of volcanic activity indicates their subvolcanic origins.
- One of the best exposed and studied ring dikes is the Loch Bà ring dike, Isle of Mull, Scotland
- The ring dikes in the Pawtuckaway State Park and the Ossipee Mountains of New Hampshire
- The Pilanesberg Game Reserve in the North West Province of South Africa
- The Ring of Gullion in southern County Armagh, Northern Ireland