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) Source:[1]