The 2003–04 First League of Serbia and Montenegro was the second and first full season of the Serbia and Montenegro's top-level football league since its establishment. It was contested by 16 teams, and Red Star Belgrade won the championship.
Rad, Čukarički, Javor Ivanjica, Rudar, Mogren and Radnički Niš were relegated to the 2003–04 Second League of Serbia and Montenegro.
The relegated teams were replaced by 2002–03 Second League of Serbia and Montenegro east, west, south and north champions Budućnost Banatski Dvor, Napredak Kruševac, Kom and Borac Čačak.
Champions: Red Star Belgrade (Coach: Slavoljub Muslin)
Players (league matches/league goals)
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Dušan Basta Nikola Beljić Dragan Bogavac
Jadranko Bogičević Branko Bošković Nemanja Vidić Milivoje Vitakić Vladimir Dišljenković (goalkeeper) Ivan Dudić Milan Dudić
Bojan Djordjic Slavoljub Đorđević Nikola Žigić Dejan Ilić Boško Janković Nenad Kovačević Radovan Krivokapić Marjan Marković Bojan Miladinović Dejan Milovanović Dragan Mladenović Dragan Mrđa
Marko Muslin Sanibal Orahovac Marko Pantelić Marko Perović Ivan Ranđelović (goalkeeper) Nenad Stojanović Dragan ŠaracSource:[1]
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