Group A: The four teams in the Série A and Série B (Internacional, Grêmio, Caxias and Juventude) played each other in a double round-robin system; the two best teams qualified into the Semifinals.
Group B: The fourteen teams that didn't participate in the Série A or Série B played against each other in a double round-robin system. After 26 rounds, the two best teams qualified to the Semifinals and the bottom two teams were relegated.
Semifinals: The four remaining teams played in a two matches to define the teams that would qualify to the Finals. In case of ties, group leaders would advance.
Finals: Semifinals winners played in two matches to define the Champions. The team with best overall record played the second leg at home.
Updated to match(es) played on March 16, 2003. Source: RSSSF.com Rules for classification: 1) points; 2) wins; 3) goal difference; 4) number of goals scored.
Updated to match(es) played on June 29, 2003. Source: RSSSF.com Rules for classification: 1) points; 2) wins; 3) goal difference; 4) number of goals scored.