Sremski Karlovci (German: Karlowitz or Carlowitz; Hungarian Karlóca, Turkish Karlofça) is a town in the autonomous province Vojvodina, Serbia and Montenegro, situated on the bank of the river Danube, between Belgrade and Novi Sad. In 2002, its population was 8,839.

Between November 16, 1698, and January 26, 1699, the town of Sremski Karlovci was the site of a congress that ended the hostilities between the Ottoman Empire and the Holy League, a coalition of various European powers including Austria, Poland, Venice and Russia; the congress produced the Treaty of Karlowitz.

The town was also the spiritual and cultural center of the Serbs in the Austro-Hungarian Empire. The Metropolitan of the Serb Orthodox Church resided in the town which also housed a seminary which operates to this day. It also featured of the earliest Serb (and Slavic in general) grammar schools (sr: gimnazija/гимназија, fr: lycée) founded on August 3rd, 1791. To this day, the Serb Orthodox Patriarch retains the title of Metropolitan of (Sremski) Karlovci.