The city of Monroe is the parish seat of Ouachita Parish, in the US state of Louisiana. It is the principal city of and is included in the Monroe, Louisiana Metropolitan Statistical Area (pop. 171,188), which is included in the Monroe-Bastrop, Louisiana Combined Statistical Area. Monroe's Combined Statistical Area is 202,209. As of the 2000 census, the city had a total population of 52,027, making it the eighth largest city in Louisiana. Monroe and the neighboring town of West Monroe (pop. 13,250), which sits just across the Ouachita River, are often referred to as the Twin Cities of northeast Louisiana.

As of the census of 2000, there are 53,107 people, 19,421 households, and 12,157 families residing in the city. The population density is 714.9/km² (1,851.8/mi²). There are 21,278 housing units at an average density of 286.5/km² (741.9/mi²). The racial makeup of the city is 36.78% White, 61.13% African American, 0.13% Native American, 1.05% Asian, 0.03% Pacific Islander, 0.25% from other races, and 0.63% from two or more races. 1.01% of the population are Hispanic or Latino of any race.