| Tourney Name: | AFC Cup |
| Year: | 2004 |
| Num Teams: | 18 |
| Associations: | 11 |
| Champion Other: |  Al-Jaish |
| Count: | 1 |
| Second Other: | Al-Wahda |
| Matches: | 61 |
| Goals: | 178 |
| Top Scorer: | Indra Sahdan Daud Egmar Gonçalves |
| Nextseason: | 2005 |
The 2004 AFC Cup was the first edition of the AFC Cup, played by clubs from nations who are members of the Asian Football Confederation.
The 'developing' 14 nations in the Asian Football Confederation were invited to nominate one or two clubs to participate in the 2004 competition.
| 2002–03 Syrian League champions | ||
| Al-Wahda | 2002–03 Syrian Cup winners | |
| 2002–03 Lebanese Premier League champions 2003 Lebanese FA Cup winners | ||
 Al-Nejmeh | 2002–03 Lebanese Premier League runners-up | |
| 2002–03 Omani League champions | ||
| 2002–03 Yemeni League champions | ||
 Muktijoddha Sangsad | 2003 Bangladesh National Football League champions 2003 Bangladesh Federation Cup winners | |
 East Bengal | 2002–03 Indian National Football League champions | |
| 2003 Indian Federation Cup winners | ||
| 2003 Turkmenistan League champions | ||
 Nebitçi Balkanabat | 2003 Turkmenistan Cup winners |
| 2002–03 Hong Kong First Division League champions | ||
 Valencia | 2003 Dhivehi League champions | |
| Island FC | 2003 Maldives FA Cup winners | |
 Perak | 2003 Malaysia Premier 1 League champions | |
| Negeri Sembilan | 2003 Malaysia FA Cup winners | |
 Home United | 2003 S.League champions 2003 Singapore Cup winners | |
| Geylang United | 2003 S.League runners-up |
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1Al Sha'ab Ibb were awarded a 3–0 win as Muktijoddha Sangsad KS did not show up for the match.
2The match was cancelled after a general strike in Yemen left Al Sha'ab Ibb unable to show up for the match.
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Three best runners-up, one from groups A, B and C and two from groups D and E, qualify for the quarter-finals.
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3–3 on aggregate; Al-Wahda won on away goals.----
Geylang United won 5–3 on aggregate.----
Al-Jaish won 3–0 on aggregate.----
Home United won 5–4 on aggregate.----
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Al-Wahda won 2–1 on aggregate.----
Al-Jaish won 6–1 on aggregate.----
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3–3 on aggregate; Al-Jaish won on away goals.
| Rank | Player | Club | Total | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | Indra Sahdan Daud | Home United | 1 | 1 | 3 | 2 | 7 | |||||||||
| Egmar Goncalves | Home United | 3 | 2 | 1 | 1 | 7 | ||||||||||
| 3 |  Cristiano Júnior | East Bengal | 2 | 2 | 1 | 1 | 6 | |||||||||
 Frank Seator | Perak | 2 | 1 | 1 | 1 | 1 | 6 | |||||||||
| Mohammad Kassas | Al-Nejmeh | 1 | 2 | 1 | 1 | 1 | 6 | |||||||||
| 6 | Moussa Traoré | Al-Wahda | 2 | 1 | 1 | 1 | 5 | |||||||||
 Aleksandar Durić | Geylang United | 1 | 1 | 1 | 1 | 1 | 5 |