Troubridge Island is an island located in the south west corner of Gulf St Vincent in South Australia near the eastern edge of the Troubridge Shoals off the east coast of Yorke Peninsula about 8 kilometres (5.0 mi) southeast by east of the town of Edithburgh It is notable for being a site of an operating lighthouse from 1856 until 2002 and as a site for a sea bird rookery.

The island is most accessible at high tide, when there is sufficient water over the intertidal zone to allow a boat reach the permanently dry land.

Since 1988, access to the island has been restricted to these with permits provided by the Department of Environment, Water and Natural Resources.

The vegetation consists of low shrubland dominated by nitre bush, grey saltbush and African boxthorn.

Other prominent plants present are tree mallow, sea rocket, marram grass and hairy spinifex.

"[8] The following reptile species have been recorded on Troubridge Island: marbled geckos and sleepy lizards.

[9] A census conducted in 2013 estimated a total population of 270 breeding adults, showing a severe and unexplained decline.

When the Parsee was wrecked on the shoals on 13 November 1838 the survivors landed at the adjacent Troubridge Island.