|Area||4827 km² (1863.72 sq mi)|
|Population||3,093,698 (2003 Census)|
Ouest (English: West, Haitian Creole: Lwès) is one of the ten departments (French: départements) of Haiti. It is the jurisdictional seat of the national capital, the city of Port-au-Prince. It has an area of and a population of 3,093,698 (2003 Census). It borders the Dominican Republic to the east.
It is the second largest department in Haiti after the department of Artibonite. Gonâve Island is also part of the Ouest Department. The department's stretch of coastline lies entirely in the Gulf of Gonâve.
(with 2003 Census populations in parenthesis)
On 12 January 2010, a magnitude 7.0 earthquake struck in the department, the largest in Haiti in two centuries.  In the Port-au-Prince Arrondissement, many areas suffered damage.  In the Léogâne Arrondissement, the city of Léogane suffered 80-90% destruction. Other places in Léogâne were also affected.