The Shetland wren (Troglodytes troglodytes zetlandicus) is a small passerine bird in the wren family. It is a subspecies of the Eurasian wren endemic to the Shetland archipelago of Scotland, with the exception of Fair Isle which has its own endemic subspecies, the Fair Isle wren.
The Shetland wren is distinguished by its darker and more rufous-brown colouring from the mainland form, with a heavily barred underside, the barring extending from belly to breast. The bill is stouter and longer and it has stronger legs.
The main breeding habitat of Shetland wrens is boulder beaches, though when population levels increase some birds will nest further inland.
An estimate of the population, from the start of the 21st century, was of 1500-3000 breeding pairs.