Republika Srpska (Serbian Cyrillic: Република Српска, pronounced [repǔblika sr̩pska]) is one of the two entities of Bosnia and Herzegovina, the other being the Federation of Bosnia and Herzegovina. Its largest city and administrative centre is Banja Luka, lying on the Vrbas river.

The entity encompasses most of the Serbs of Bosnia and Herzegovina-populated portions of Bosnia and Herzegovina situated in the north and east of the country. Formed in 1992 at the outset of the breakup of Yugoslavia, Republika Srpska, following the Dayton Accords, achieved international recognition as part of a federal Bosnia and Herzegovina.

Today, Republika Srpska maintains a parliamentary-style government, with the National Assembly holding legislative power within the entity. Republika Srpska is relatively centralised, although it is split into 2nd-level administrative units—municipalities, or opštine—of which there are 64. The legislature holds 83 seats, and the current session is the ninth since its founding.