| Tournament details | |
|---|---|
| Dates | 8 March - 5 November 2005 |
| Teams | 29 |
| Final positions | |
| Champions |
|
| Runners-up |
|
| Tournament statistics | |
| Matches played | 98 |
| Goals scored | 286 (2.92 per match) |
| Top scorer(s) |
(6 goals) |
The 2005 AFC Champions League was the 24th edition of the top-level Asian club football tournament and the 3rd edition under the current AFC Champions League title. The championship was retained by the Saudi Arabian club Al-Ittihad with a 5-3 aggregate victory over UAE side Al Ain. Following a 1-1 draw at the Tahnon Bin Mohammed Stadium in Al Ain in the first leg, Al-Ittihad recorded a 4-2 victory at the Prince Abdullah Al Faisal Stadium in Jeddah to lift the trophy for the second consecutive season. They also qualifed for the 2005 FIFA Club World Cup.
A total of 28 clubs were divided into 7 groups of four, based on region i.e. East Asian and Southeast Asian clubs were drawn in groups E to G, while the rest were grouped in groups A to D. Each club played double round-robin (home and away) against fellow three group members, a total of 6 matches each. Clubs received 3pts for a win, 1pt for a tie, 0pts for a loss. The clubs were ranked according to points and tie breakers were in the following order:
The seven group winners along with the defending champion advanced to the quarter-finals.
All 8 clubs were randomly matched; however, the only restriction was that the clubs from the same country could not face each other in the quarter-finals. The games were conducted in 2 legs, home and away, and the aggregate score decided the match winner. If the aggregate score couldn't produce a winner, "away goals rule" was used. If still tied, clubs played extra time, where "away goals rule" still applied. If still tied, the game went to penalties.
1: awarded 3–0 to Neftchi because Al-Ahli failed to show up.