| Doubles | |
|---|---|
| 2004 Mercedes-Benz Cup | |
| Champions |  Bob Bryan Mike Bryan |
| Runners-up |  Wayne Arthurs Paul Hanley |
| Final score | 6–3, 7–6(8–6) |
| Draw | 16 |
| Seeds | 4 |
Jan-Michael Gambill and Travis Parrott were the defending champions, but Gambill did not participate this year. Parrott partnered Robby Ginepri, losing in the first round.
Bob Bryan and Mike Bryan won in the final 6–3, 7–6(8–6), against Wayne Arthurs and Paul Hanley.
Bob Bryan / Mike Bryan (champions) Wayne Arthurs / Paul Hanley (final)
Jonathan Erlich / Andy Ram (semifinals)
Mark Merklein / 
Martín Rodríguez (first round)| First round | Quarterfinals | Semifinals | Final | ||||||||||||||||||||||||
| 1 | B Bryan M Bryan | 6 | 77 | ||||||||||||||||||||||||
| WC | A Bogomolov Jr. T Dent | 2 | 62 | 1 | B Bryan M Bryan | 6 | 66 | 6 | |||||||||||||||||||
 R Koenig  T Shimada | 3 | 6 | 6 | R Koenig T Shimada | 2 | 78 | 1 | ||||||||||||||||||||
| M Fish J Morrison | 6 | 4 | 3 | 1 | B Bryan M Bryan | 77 | 7 | ||||||||||||||||||||
| 3 | J Erlich A Ram | 6 | 77 | 3 | J Erlich A Ram | 64 | 5 | ||||||||||||||||||||
| J Kerr J Thomas | 3 | 61 | 3 | J Erlich A Ram | 6 | 6 | |||||||||||||||||||||
| R Leach B MacPhie | 77 | 4 | 6 | R Leach B MacPhie | 2 | 3 | |||||||||||||||||||||
| S Humphries G Oliver | 65 | 6 | 3 | 1 | B Bryan M Bryan | 6 | 78 | ||||||||||||||||||||
| WC |  H-t Lee T Phillips | 62 | 6 | 2 | W Arthurs P Hanley | 3 | 66 | ||||||||||||||||||||
 T Haas G Weiner | 77 | 2 | r | WC | H-t Lee T Phillips | 6 | 6 | ||||||||||||||||||||
 J Benneteau G Carraz | 3 | 6 | 77 | J Benneteau G Carraz | 4 | 1 | |||||||||||||||||||||
| 4 | M Merklein M Rodríguez | 6 | 3 | 64 | WC | H-t Lee T Phillips | 6 | 1 | 62 | ||||||||||||||||||
| R Ginepri T Parrott | 4 | 6 | 5 | 2 | W Arthurs P Hanley | 4 | 6 | 77 | |||||||||||||||||||
N Kiefer  P Srichaphan | 6 | 4 | 7 | N Kiefer P Srichaphan | 77 | 3 | 4 | ||||||||||||||||||||
 K Beck D Hrbatý | 78 | 4 | 4 | 2 | W Arthurs P Hanley | 63 | 6 | 6 | |||||||||||||||||||
| 2 | W Arthurs P Hanley | 66 | 6 | 6 | |||||||||||||||||||||||
Michaël Llodra and Fabrice Santoro were the defending champions, but they lost in quarterfinals 6–7(2), 5–7, against Jonas Björkman and Max Mirnyi.
First-seeded Bob Bryan and Mike Bryan defeated seventh-seeded Martin Damm and Leander Paes 4–6, 6–3, 6–4 to win the men's doubles title at the 2006 Australian Open.
Jeff Coetzee and Chris Haggard were the defending champions but did not compete that year.
Michaël Llodra and Fabrice Santoro were the defending champions, and won the final 7–6(4), 6–3 against Bob and Mike Bryan.
Mahesh Bhupathi and Leander Paes were the defending champions but only Paes competed that year with John-Laffnie de Jager.
James Blake and Todd Martin were the defending champions but lost in the second round to Wayne Arthurs and Paul Hanley.
Paul Hanley and Nathan Healey were the defending champions but they competed with different partners that year, Hanley with Wayne Arthurs and Healey with Jordan Kerr.
Wayne Arthurs and Paul Hanley were the defending champions, but lost in the first round this year.
Rick Leach and Brian MacPhie were the defending champions, but lost in the first round this year.
Bob Bryan and Mike Bryan were the defending champions, but lost in the semifinals this year.
Bob Bryan and Mike Bryan were the defending champions, but lost in the semifinals this year.
Bob Bryan and Mike Bryan were the defending champions and successfully defended their title, defeating Jonas Björkman and Max Mirnyi 7–6(11–9), 7–6(7–4) in the final.
Mark Knowles and Daniel Nestor were the defending champions.
Arnaud Clément and Sébastien Grosjean were the defending champions, but did not partner together this year. Clément partnered Jaroslav Levinský, losing in the first round. Grosjean partnered Gaël Monfils, losing in the second round.
Wayne Black and Kevin Ullyett were the defending champions, but lost in the final this year..
Mark Knowles and Daniel Nestor were the defending champions, but lost in the first round to Paul Goldstein and Jim Thomas.
Mahesh Bhupathi and Max Mirnyi were the defending champions, but lost in the quarterfinals to Michaël Llodra and Fabrice Santoro.
Bob and Mike Bryan were the defending champions, but lost in second round to Jonathan Erlich and Andy Ram.
Mark Knowles and Daniel Nestor were the defending champions, but lost in Quarterfinals to Wayne Black and Kevin Ullyett.
Mahesh Bhupathi and Max Mirnyi defeated defending champions Wayne Arthurs and Paul Hanley 2–6, 6–3, 6–4 in the final. It was the 34th title for Bhupathi and the 20th title for Mirnyi in their respective careers.