2005 Campeonato Ecuatoriano de Fútbol Serie A

Campeonato Apertura

The Apertura tournament was set into two stages. The First Stage was a double round-robin tournament where each team plays the other nine teams twice, once at home and once away. The top eight teams advanced to a two-leg single elimination knockout stage. The last team in the First Stage was relegated to Serie B. The winner of the knockout stage is the Apertura champion, and qualifies as the Ecuador 1 berth in the 2006 Copa Libertadores.

First stage

Playoff stage

| RD1-seed1=1 | RD1-team1=LDU Quito | RD1-score1-1=1 | RD1-score1-2=5 | RD1-score1-agg=6 | RD1-seed2=8 | RD1-team2=Olmedo | RD1-score2-1=1 | RD1-score2-2=1 | RD1-score2-agg=2

| RD1-seed3=4 | RD1-team3=Deportivo Cuenca* | RD1-score3-1=1 | RD1-score3-2=3 | RD1-score3-agg=4 | RD1-seed4=5 | RD1-team4=LDU Loja | RD1-score4-1=1 | RD1-score4-2=3 | RD1-score4-agg=4

| RD1-seed5=3 | RD1-team5=Barcelona* | RD1-score5-1=0 | RD1-score5-2=2 | RD1-score5-agg=2 | RD1-seed6=6 | RD1-team6=Deportivo Quito | RD1-score6-1=2 | RD1-score6-2=0 | RD1-score6-agg=2

| RD1-seed7=2 | RD1-team7=El Nacional | RD1-score7-1=0 | RD1-score7-2=4 | RD1-score7-agg=4 | RD1-seed8=7 | RD1-team8=Aucas | RD1-score8-1=0 | RD1-score8-2=0 | RD1-score8-agg=0

| RD2-seed1=1 | RD2-team1=LDU Quito | RD2-score1-1=1 | RD2-score1-2=3 | RD2-score1-agg=4 | RD2-seed2=4 | RD2-team2=Deportivo Cuenca | RD2-score2-1=2 | RD2-score2-2=1 | RD2-score2-agg=3

| RD2-seed3=3 | RD2-team3=Barcelona | RD2-score3-1=1 | RD2-score3-2=2 | RD2-score3-agg=3 | RD2-seed4=2 | RD2-team4=El Nacional | RD2-score4-1=1 | RD2-score4-2=1 | RD2-score4-agg=2

| RD3-seed1=1 | RD3-team1=LDU Quito | RD3-score1-1=0 | RD3-score1-2=3 | RD3-score1-agg=3 | RD3-seed2=3 | RD3-team2=Barcelona | RD3-score2-1=1 | RD3-score2-2=0 | RD3-score2-agg=1

() Barcelona and D. Cuenca advance because of better First Stage records.*

Campeonato Clausura

The Clausura tournament was set into two stages. The First Stage was a double round-robin tournament where each team played the other nine teams twice, once at home and once away. The top six teams in the First Stage advanced to the Liguilla Final, with the top three earning bonus points (3, 2, and 1 point respectively). The last team in the First Stage was relegated to Serie B. The winner of the Liguilla Final was the Clausura champion. The champion and runner-up qualified as the Ecuador 2 and Ecuador 3 berth in the 2006 Copa Libertadores. ESPOLI was promoted to Serie A at the end of Serie B's 2005 Apertura tournament.

First stage

Liguilla Final