Lanester (French pronunciation: [lanɛstɛʁ]; Breton: Lannarstêr) is a commune in the Morbihan department in Brittany, in north-western France.

[3] It is the largest suburb of the city of Lorient, across the river Scorff to the east.

The mouth of river Blavet forms a natural boundary to the east and to the south.

Lanester was created later than Lorient, with the development of shipyards on the left bank of the river Scorff in the middle of the nineteenth century.

The municipality created a linguistic plan through Ya d'ar brezhoneg on 13 July 2006.