Ribnik (Serbian Cyrillic: Рибник) is a municipality in Republika Srpska, Bosnia and Herzegovina.

It is situated in the southern part of the Bosanska Krajina region.

Ribnik, briefly known as Srpski Ključ (Српски Кључ), was created from part of the pre-war municipality of Ključ (the other part of the pre-war municipality is now in the Federation of Bosnia and Herzegovina).

It is located between municipalities of Oštra Luka in the north, Banja Luka and Mrkonjić Grad in the east, Glamoč in the south, and Istočni Drvar, Bosanski Petrovac, and Ključ in the west.

[1] Una-Sana  Central Bosnia Posavina  Herzegovina-Neretva Tuzla  West Herzegovina Zenica-Doboj  Sarajevo Bosnian Podrinje Canton 10