Ruwi Club were the defending champions, having won the 2002–03 Omani League season.
won 2–1 at home in their final league match against Al-Oruba SC and resulted as the champions of the 2003–04 Omani League with a total of 46 points.
This season the number of teams in the league had decreased from 14 to 12.
Nizwa Club, Sidab Club, Al-Salam SC and Al-Ahli Club were relegated to the Second Division League after finishing in the relegation zone in the 2002–03 season.
The four relegated teams were replaced by Second Division League teams Al-Tali'aa SC and Al-Nahda Club.