Due to its long history, Banja Luka has a rich culture. A number of museums can be found in the city, including the Museum of Republika Srpska also known as the Museum of Bosanska Krajina, and the Ethnographic Museum, established in 1930. Banja Luka also has a national theatre, and library, both dating from the first half of the 20th century. There are numerous other museums and theatres in the city including the Museum of Modern Art of Republika Srpska.

One of the most famous cultural sites in Banja Luka is the cultural centre "Banski Dvor" (Halls of the Ban), built in the 1930s as a spot of residence for the Bans of the Vrbas Banovina. It is a beautiful building in the very center of the city. The National Assembly is inside, along with a concert hall, gallery, state television, and restaurant. Most of the main cultural and political leadership nowadays takes place inside of the building.

The relatively poorly preserved fortress Kastel is found in the center of the city. This medieval castle is one of Banja Luka’s main attractions but has recently become a gathering spot for drug addicts. Located on the bank of the Vrbas River, it gave specific charm to the city. During the summer some concerts took place in the fortress.

In the city there are many Cultural Artistic Associations. The oldest is RKUD "Pelagic" (1927), and it is the oldest institution of this kind in Bosnia and Herzegovina.