Île Seguin (French pronunciation: [il səɡɛ̃], Seguin Island) is an island on the Seine river between Boulogne-Billancourt and Sèvres, in the west suburbs of Paris, France. It has a surface area of approximately 11.5 hectares (28 acres), and is positioned opposite Meudon, a short distance downstream from the Île Saint-Germain. Administratively Meudon and the island are included as part of Boulogne-Billancourt, on the river's right bank, rather than of Sèvres on the left bank.
During most of the twentieth century, Île Seguin was home to a Renault factory, covering virtually the whole island. The last car from the Renault production line was a 1992 Renault 5 Supercinq. The factory remained dormant until 2005 when all the buildings were demolished.
