Thorness Bay is an 213-acre (86.2-hectare) Site of special scientific interest which is located on the north-west coast of the Isle of Wight, England, in the western arm of the Solent.

The bay stretches about 2 miles (3.2 km) from Salt Mead Ledge in the west to Gurnard Head Nr.

The sea bed is a mixture of mud, sand and shingle with rocky outcrops of Bembridge Limestone.

[1][2] A small unnamed brook enters the sea in the middle of the bay after passing through a marsh.

This article about a Site of Special Scientific Interest in England is a stub.