The Nitra (Slovak: Nitra, , ) is a long river in western Slovakia. It flows into the Váh river close to its confluence with the Danube in Komárno. Its source is in the Malá Fatra (Lesser Fatra) mountains north of Prievidza. The river Nitra passes through the towns of Bojnice, Topolcany, Nitra and Nové Zámky.